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Multiple Type Support

PHP

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Tutorial Hierarchy

PHP Introduction
- Overview
  - Definition
    
    What is PHP
  - Full Form
    
    PHP Hypertext Preprocessor
- History
  - Created By
    
    PHP Created by Rasmus Lerdorf
  - Year 1994
    
    PHP First Released 1994
  - PHP 3
    
    PHP 3 Released 1998
  - PHP 4
    
    PHP 4 with Zend Engine
  - PHP 5
    
    PHP 5 Object Oriented
  - PHP 7
    
    PHP 7 Performance Boost
  - PHP 8
    
    PHP 8 with JIT
- Use Cases
  - Web Development
    
    Server Side Web Apps
  - CLI Scripts
    
    Command Line Applications
  - API Development
    
    RESTful API Services
  - Desktop Apps
    
    PHP GTK Applications
- Advantages
  - Open Source
    
    PHP is Free to Use
  - Cross Platform
    
    Runs on All OS
  - Easy Learning
    
    Simple PHP Syntax
  - Community Support
    
    Large Developer Community
  - Database Support
    
    Supports Many Databases
  - Hosting Support
    
    PHP on Most Hosting
- Disadvantages
  - Security Issues
    
    Requires Careful Coding
  - Not for Real Time
    
    Not Best for Real Time
  - Inconsistent Names
    
    Function Name Inconsistencies
  - No Multithreading
    
    Lacks Built-in Multithreading
- Comparison
  - vs JavaScript
    
    PHP Server Side vs Client Side
  - vs Python
    
    PHP Web vs Python General
  - vs Node.js
    
    PHP Sync vs Node Async
  - vs ASP.NET
    
    PHP Open Source vs Microsoft
PHP Installation
- XAMPP
  - Download
    
    Download XAMPP from Apache Friends
  - Installation
    
    Run XAMPP Installer
  - Control Panel
    
    Start Apache and MySQL
  - htdocs Folder
    
    Web Root Directory
  - phpMyAdmin
    
    Access Database Manager
  - Localhost Access
    
    Open http://localhost
- WAMP
  - Download
    
    Download WAMP from Sourceforge
  - Installation
    
    RUN WAMP Installer
  - www Folder
    
    Web Root Directory
  - Tray Icon
    
    Green Icon Shows Services Running
  - phpMyAdmin
    
    Database Management Tool
- LAMP
  - Ubuntu Installation
    
    sudo apt-get install lamp-server
  - Apache Start
    
    sudo systemctl start apache2
  - MySQL Start
    
    sudo systemctl start mysql
  - Web Root
    
    /var/www/html Directory
- MAMP
  - Download
    
    Download MAMP for macOS
  - Installation
    
    Drag to Applications Folder
  - Start Servers
    
    Click Start Servers Button
  - htdocs Folder
    
    Web Root in MAMP Folder
- Docker
  - PHP Image
    
    docker pull php
  - Run Container
    
    docker run -d -p 80:80 php
  - Docker Compose
    
    Use docker-compose.yml
- Manual
  - Windows Download
    
    Download from php.net
  - Windows Extract
    
    Extract to C:\php
  - Add to PATH
    
    Add PHP to Environment Path
  - Linux PPA
    
    sudo add-apt-repository ppa:ondrej/php
  - Linux Install
    
    sudo apt-get install php8.2
  - macOS Brew
    
    brew install php
- Verification
  - Version Command
    
    php -v Check Version
  - Info Function
    
    phpinfo Display Configuration
  - Modules List
    
    php -m Show Modules
- Configuration
  - php.ini File
    
    PHP Configuration File
  - Find php.ini
    
    php --ini Location
  - Common Settings
    
    Set memory_limit and upload size
PHP Syntax
- Opening Tags
  - Standard Tag
    
    <?php Standard Opening
  - Short Tag
    
    <? Short Tag Deprecated
  - Echo Short Tag
    
    <?= Echo Shortcut
  - Script Tag
    
    <script language="php"> Deprecated
- Closing Tags
  - Standard Closing
    
    ?> Closing Tag
  - Omission
    
    Omit in Pure PHP Files
  - Whitespace Issue
    
    No Whitespace After Closing Tag
- Statements
  - Semicolon Required
    
    Statement Terminator
  - Last Semicolon
    
    Last Statement Semicolon Optional
- Whitespace
  - Spaces Ignored
    
    Whitespace Insensitive
  - Tabs Ignored
    
    Tabs Are Insensitive
  - Newlines Ignored
    
    Newlines Are Insensitive
- Case Sensitivity
  - Variables Case Sensitive
    
    $name vs $NAME Different
  - Functions Not Sensitive
    
    User Functions Case Insensitive
  - Classes Not Sensitive
    
    Class Names Case Insensitive
  - Constants Case Sensitive
    
    Constants Case Sensitive by Default
- Comments
  - Single Line
    
    // Double Slash Comment
  - Single Line Hash
    
    # Shell Style Comment
  - Multi Line
    
    /* */ Block Comment
  - DocBlock
    
    /** */ Documentation Comment
  - PHPDoc
    
    Documentation for Functions Classes
PHP Variables
- Syntax
  - Dollar Prefix
    
    $ Sign Required
  - Assignment Operator
    
    #NAME?
- Naming Rules
  - First Character
    
    Start with Letter or Underscore
  - Next Characters
    
    Letters Numbers Underscores
  - Reserved Keywords
    
    Cannot Use Keywords as Names
- Valid Examples
  - Simple Variable
    
    $name
  - With Underscore
    
    $first_name
  - With Numbers
    
    $var123
  - Camel Case
    
    $firstName
- Invalid Examples
  - Starting Number
    
    $123name
  - Special Characters
    
    $name$
  - Space in Name
    
    $na me
  - Hyphen Character
    
    $first-name
- Case Sensitivity
  - Different Variables
    
    $name vs $NAME Different
  - Common Mistake
    
    Wrong Case Causes Error
- Assignment
  - Value Assignment
    
    $name = "John"
  - Copy by Value
    
    Copies Value to New Variable
  - Copy by Reference
    
    & Creates Reference
- Variable Variables
  - Double Dollar
    
    $$var Dynamic Name
  - Complex Syntax
    
    ${$x} Syntax
- Variable References
  - Reference Operator
    
    & Creates Reference
  - Reference Behavior
    
    Both Point to Same Data
- Variable Scope
  - Local Scope
    
    Inside Function Only
  - Global Scope
    
    Outside Functions Only
  - Function Parameters
    
    Local to Function
  - Static Variables
    
    Persistence Between Calls
  - Global Keyword
    
    Access Global Inside Function
  - GLOBALS Array
    
    $GLOBALS['var'] Access Anywhere
- Variable Functions
  - isset Function
    
    Check Variable Set Not Null
  - empty Function
    
    Check Variable Empty
  - unset Function
    
    Destroy Variable
  - is_null Function
    
    Check if NULL
- Predefined Variables
  - Superglobals
    
    Available Everywhere
  - $GLOBALS Array
    
    All Global Variables
  - $_SERVER Array
    
    Server Environment Variables
  - $_GET Array
    
    HTTP GET Parameters
  - $_POST Array
    
    HTTP POST Parameters
  - $_FILES Array
    
    File Upload Variables
  - $_COOKIE Array
    
    HTTP Cookies
  - $_SESSION Array
    
    Session Variables
  - $_REQUEST Array
    
    GET POST COOKIE Combined
  - $_ENV Array
    
    Environment Variables
PHP Constants
- define Function
  - Syntax
    
    define('NAME'
  - Case Insensitive
    
    Third Parameter Deprecated
  - Return Value
    
    Returns true on Success
- const Keyword
  - Syntax
    
    const NAME = value
  - Compile Time
    
    Defined at Compile Time
  - Class Constants
    
    Only const in Classes
- Naming Conventions
  - Uppercase
    
    UPPERCASE_WITH_UNDERSCORES
  - No Dollar Sign
    
    No $ Prefix
- Scope
  - Global Scope
    
    Constants Automatically Global
  - Function Scope
    
    Constants Accessible Inside Functions
- Constants vs Variables
  - No $ Sign
    
    Constants Don't Use $
  - Global by Default
    
    Constants Always Global
  - Cannot Change
    
    Constants Cannot Be Reassigned
  - Value Types
    
    Constants Support Limited Types
- Checking Constants
  - defined Function
    
    Check if Constant Exists
  - constant Function
    
    Get Constant Value
  - constants Function
    
    Get All Defined Constants
- Magic Constants
  - __LINE__
    
    Current Line Number
  - __FILE__
    
    Current File Path
  - __DIR__
    
    Current Directory Path
  - __FUNCTION__
    
    Current Function Name
  - __CLASS__
    
    Current Class Name
  - __METHOD__
    
    Current Method Name
  - __NAMESPACE__
    
    Current Namespace Name
  - __TRAIT__
    
    Current Trait Name
PHP Data Types
- String Type
  - Definition
    
    Sequence of Characters
  - Quotes
    
    Single or Double Quotes
  - Heredoc
    
    Multi-line String
  - Nowdoc
    
    No Parsing String
- Integer Type
  - Definition
    
    Whole Numbers
  - Ranges
    
    64-bit Range
  - Decimal
    
    Base 10 Numbers
  - Hexadecimal
    
    0x Prefix
  - Octal
    
    0 Prefix
  - Binary
    
    0b Prefix
- Float Type
  - Definition
    
    Decimal Numbers
  - Also Called
    
    Double or Real
  - Ranges
    
    Approximate Range
  - Precision
    
    14 Decimal Digits
- Boolean Type
  - Definition
    
    Truth Values
  - Values
    
    true or false
  - Case Insensitive
    
    TRUE true Same
  - Truthy Values
    
    Non-zero Non-empty Values
- Array Type
  - Definition
    
    Key Value Pairs
  - Indexed Array
    
    Numeric Keys from 0
  - Associative Array
    
    String Keys
  - Multidimensional
    
    Arrays Inside Arrays
- Object Type
  - Definition
    
    Class Instance
  - Creation
    
    new Keyword
  - Property Access
    
    -> Operator
  - Method Call
    
    -> Operator
- NULL Type
  - Definition
    
    No Value
  - Assignment
    
    $var = null
  - Case Insensitive
    
    NULL null Same
  - Unset Variable
    
    Variable Without Value
- Resource Type
  - Definition
    
    External Resource
  - Examples
    
    Database File Handles
  - Not Serializable
    
    Cannot Serialize
- Type Checking
  - gettype Function
    
    Returns Type String
  - var_dump Function
    
    Prints Type and Value
  - print_r Function
    
    Human Readable Output
  - debug_zval_dump
    
    Dump with Reference Count
  - is_string Function
    
    Check if String
  - is_int Function
    
    Check if Integer
  - is_float Function
    
    Check if Float
  - is_bool Function
    
    Check if Boolean
  - is_array Function
    
    Check if Array
  - is_object Function
    
    Check if Object
  - is_null Function
    
    Check if NULL
  - is_resource Function
    
    Check if Resource
  - is_numeric Function
    
    Check if Number String
  - is_scalar Function
    
    Check if Scalar Type
  - is_callable Function
    
    Check if Callable
  - is_iterable Function
    
    Check if Iterable
  - is_countable Function
    
    Check if Countable
PHP Type Casting
- Explicit Casting
  - String to Integer
    
    (int) Casting
  - String to Float
    
    (float) Casting
  - String to Boolean
    
    (bool) Casting
  - Integer to String
    
    (string) Casting
  - Integer to Array
    
    (array) Casting
  - Integer to Object
    
    (object) Casting
  - Array to Object
    
    (object) Casting
  - Object to Array
    
    (array) Casting
- Casting Functions
  - intval Function
    
    Get Integer Value
  - floatval Function
    
    Get Float Value
  - boolval Function
    
    Get Boolean Value
  - strval Function
    
    Get String Value
- Type Juggling
  - Automatic Conversion
    
    PHP Converts Types Automatically
  - String to Number
    
    10 + 5
  - Number to String
    
    echo 10 . items
- settype Function
  - settype Usage
    
    Change Variable Type Permanently
  - settype Example
    
    settype($var
  - Return Value
    
    Returns true on Success
PHP Operators
- Arithmetic
  - Addition
    
    Plus Operator
  - Subtraction
    
    Minus Operator
  - Multiplication
    
    Asterisk Operator
  - Division
    
    Forward Slash Operator
  - Modulus
    
    Percent Operator
  - Exponentiation
    
    Double Asterisk Operator
- Assignment
  - Simple Assign
    
    Equal Sign
  - Add and Assign
    
    Plus Equal
  - Subtract and Assign
    
    Minus Equal
  - Multiply and Assign
    
    Asterisk Equal
  - Divide and Assign
    
    Slash Equal
  - Modulus and Assign
    
    Percent Equal
  - Exponent and Assign
    
    Double Asterisk Equal
  - Concatenate and Assign
    
    Dot Equal
- Comparison
  - Equal Value
    
    Double Equal
  - Identical
    
    Triple Equal
  - Not Equal Value
    
    Exclamation Equal
  - Not Equal Alternative
    
    Less Than Greater Than
  - Not Identical
    
    Exclamation Double Equal
  - Greater Than
    
    Right Angle Bracket
  - Less Than
    
    Left Angle Bracket
  - Greater Than or Equal
    
    Right Angle Equal
  - Less Than or Equal
    
    Left Angle Equal
  - Spaceship
    
    Double Less Than Double Equal Greater Than
  - Null Coalescing
    
    Double Question Mark
- Ternary
  - Standard Ternary
    
    Question Mark Colon
  - Shorthand Ternary
    
    Question Mark Colon Colon
- Logical
  - AND
    
    Double Ampersand
  - OR
    
    Double Pipe
  - XOR
    
    Exclusive OR
  - NOT
    
    Exclamation Mark
- String
  - Concatenation
    
    Dot Operator
  - Concatenation Assignment
    
    Dot Equal
- Array
  - Union
    
    Plus Operator
  - Equal
    
    Double Equal
  - Identical
    
    Triple Equal
  - Not Equal
    
    Exclamation Equal
  - Not Identical
    
    Exclamation Double Equal
- Error Control
  - At Sign
    
    Suppress Warnings
- Execution
  - Backticks
    
    Execute Shell Command
- Instanceof
  - Type Check
    
    Check Object Class
PHP Control Structures
- if Statement
  - Basic Syntax
    
    if Condition Execute Code
  - Example Code
    
    Check Age Adult
- if else
  - Basic Syntax
    
    if else Alternative Execution
  - Example Code
    
    Pass Fail Check
- elseif
  - Basic Syntax
    
    Multiple Conditions
  - Example Code
    
    Grade Check
- Nested if
  - Definition
    
    if Inside Another if
  - Example Code
    
    Admin Logged In Check
- Alternative Syntax
  - if Colon Syntax
    
    if condition endif
  - Usage
    
    Template Files
- switch
  - Basic Syntax
    
    switch case break
  - break Keyword
    
    Prevent Fallthrough
  - default Case
    
    No Match Found
  - Multiple Cases
    
    Same Block Cases
- match
  - PHP 8 Feature
    
    Returns Value No Fallthrough
  - Default Pattern
    
    Match Default
  - Strict Comparison
    
    Triple Equal Match
PHP Loops
- while Loop
  - Syntax
    
    while condition execute
  - Example
    
    Counter Loop
  - Infinite Loop
    
    while true
- do while Loop
  - Syntax
    
    do while condition
  - Example
    
    Runs at Least Once
- for Loop
  - Syntax
    
    for init condition increment
  - Example
    
    Counter Loop
  - Multiple Variables
    
    for with Multiple Counters
- foreach Loop
  - Indexed Array
    
    foreach as value
  - Associative Array
    
    foreach as key value
  - Reference Modifier
    
    Ampersand Modify Values
  - Object Iteration
    
    foreach object properties
- break Statement
  - Basic Break
    
    Exit Current Loop
  - Break Level
    
    Exit Multiple Loops
- continue Statement
  - Basic Continue
    
    Skip Current Iteration
  - Continue Level
    
    Skip in Nested Loops
- Alternative Syntax
  - for Endfor
    
    for colon endfor
  - while Endwhile
    
    while colon endwhile
  - foreach Endforeach
    
    foreach colon endforeach
PHP Include
- include Statement
  - Basic Usage
    
    include file.php
  - Warning Only
    
    Script Continues on Error
  - Return Value
    
    File Can Return Data
- include_once
  - Basic Usage
    
    include_once file.php
  - Prevent Duplicate
    
    No Multiple Inclusions
- require Statement
  - Basic Usage
    
    require file.php
  - Fatal Error
    
    Script Stops on Error
- require_once
  - Basic Usage
    
    require_once file.php
  - Prevent Duplicate
    
    No Multiple Inclusions
- include_path
  - set_include_path
    
    Set Include Directory
  - get_include_path
    
    Get Current Path
- Return in Include
  - Return Value
    
    File Returns with return
  - Example
    
    Config File Returns Array
- __DIR__ Magic
  - Usage
    
    Include from Current Directory
  - Example
    
    require_once __DIR__ config
PHP Functions
- User Defined
  - Syntax
    
    function functionName
  - Example
    
    greet Function
- Naming Rules
  - Valid Names
    
    Start Letter Underscore
  - Invalid Names
    
    Numbers Special Chars
  - Case Insensitive
    
    greet GREET Same
- Parameters
  - Syntax
    
    function name param1 param2
  - Usage
    
    Pass Values to Function
- Return Values
  - return Statement
    
    Send Value Back
  - Example
    
    return result
  - Function Stops
    
    Code After return Ignored
- Void Function
  - No Return
    
    Returns null
- Type Declarations
  - Parameter Types
    
    int string array
  - Example
    
    function add int num
- Return Type Declaration
  - Syntax
    
    colon type
- Strict Types
  - Declaration
    
    declare strict_types 1
  - Location
    
    First Statement in File
  - Effect
    
    Type Mismatch TypeError
- Default Parameters
  - Syntax
    
    param default value
  - Example
    
    function greet name Guest
  - Right Side Only
    
    Defaults on Right
- Pass by Reference
  - Syntax
    
    ampersand param
  - Example
    
    function addFive ampersand num
  - Effect
    
    Original Variable Modified
- Variadic Parameters
  - Syntax
    
    three dots param
  - Example
    
    function sum three dots numbers
  - Usage
    
    Numbers as Array
- Named Arguments
  - PHP 8 Syntax
    
    paramName colon value
  - Example
    
    array_fill start_index 0
    
    htmlspecialchars with Named
  - Any Order
    
    Parameters Reorderable
  - PHP 8.0
    
    Parameter Name Pass
  - Skipping Defaults
    
    Skip Optional Parameters
  - Order Independence
    
    Parameters Any Order
  - Combine Positional
    
    Named After Positional
- Variable Functions
  - Syntax
    
    funcName variable
  - Example
    
    strlen via variable
- Anonymous Functions
  - Syntax
    
    function without name
  - Example
    
    assign to variable
  - Closure
    
    use keyword for scope
- Arrow Functions
  - PHP 7.4 Syntax
    
    fn param expression
  - Example
    
    fn a b a plus b
    
    fn x y x plus y
  - Implicit Return
    
    No return Keyword
  - PHP 7.4
    
    Short Closure Syntax
  - Parent Scope
    
    Automatic Variable Binding
  - No Multi Statement
    
    Single Expression Only
  - No Return Keyword
    
    Implicit Return
- Function Scope
  - Local Variables
    
    Inside Function Only
  - Global Access
    
    global Keyword
  - global Keyword Usage
    
    global varName
  - Example
    
    global count increment
- GLOBALS Array
  - $GLOBALS Usage
    
    Access Any Global
  - Example
    
    GLOBALS count increment
- Static Variables
  - static Keyword
    
    static counter
  - Behavior
    
    Persists Between Calls
  - Example
    
    countVisits Function
- Recursion
  - Definition
    
    Function Calls Itself
  - Example
    
    factorial Function
  - Limit
    
    Stack Overflow Risk
- Callback Functions
  - Definition
    
    Function as Parameter
  - call_user_func
    
    Call Callback Function
  - call_user_func_array
    
    Call with Array Parameters
  - is_callable
    
    Check if Callable
  - Closure Example
    
    Anonymous Function as Callback
  - Array Map Example
    
    Apply Callback to Array
  - Array Filter Example
    
    Filter with Callback
  - usort Example
    
    Sort with Callback
- Closure
  - Closure Class
    
    Represent Anonymous Function
  - bind Method
    
    Clone Closure with New This
  - bindTo Method
    
    Bind Closure to Object
  - call Method
    
    Call Closure Bound to Object
  - fromCallable Method
    
    Convert Callable to Closure
  - Use Case
    
    Event Handlers
    
    Currying Functions
- Variadic Functions
  - Three Dots Syntax
    
    Variable Length Arguments
  - Type Declaration
    
    Variadic with Type Hints
  - Example
    
    Sum Function
  - Before PHP 5.6
    
    func_num_args Method
  - func_num_args
    
    Count Arguments
  - func_get_arg
    
    Get Single Argument
  - func_get_args
    
    Get All Arguments
PHP Arrays
- Indexed Array
  - Definition
    
    Numeric Keys Start 0
  - array Function
    
    array Create Array
  - Short Syntax
    
    Square Brackets
  - Example
    
    $colors array red blue
  - Access Element
    
    $array index
  - Modify Element
    
    $array index new value
  - Add Element
    
    $array new index value
  - Automatic Index
    
    Largest Index Plus One
- Associative Array
  - Definition
    
    String Keys
  - array Function
    
    array key value
  - Short Syntax
    
    key value brackets
  - Example
    
    $user name John
  - Access Element
    
    $array key
  - Modify Element
    
    $array key new value
  - Add Element
    
    $array new key value
- Multidimensional Array
  - Definition
    
    Array Inside Array
  - Two Dimensional
    
    Matrix Structure
  - Three Dimensional
    
    Cube Structure
  - Access Element
    
    $array index index
  - Example
    
    Student Grades Matrix
  - Iteration
    
    Nested foreach Loops
- Array Functions
  - count Function
    
    Get Array Length
  - sizeof Alias
    
    Count Alias Function
  - array_push
    
    Add Element to End
  - array_pop
    
    Remove Element from End
  - array_shift
    
    Remove Element from Start
  - array_unshift
    
    Add Element to Start
  - array_merge
    
    Merge Multiple Arrays
  - array_merge_recursive
    
    Merge Nested Arrays
  - array_combine
    
    Keys and Values to Array
  - array_keys
    
    Get All Keys
  - array_values
    
    Get All Values
  - array_key_exists
    
    Check Key Exists
  - in_array
    
    Check Value Exists
  - array_search
    
    Search Value Return Key
  - array_reverse
    
    Reverse Array Order
  - array_slice
    
    Extract Portion of Array
  - array_splice
    
    Remove Replace Portion
  - array_unique
    
    Remove Duplicate Values
  - array_map
    
    Apply Function to Elements
  - array_filter
    
    Filter Elements by Callback
  - array_reduce
    
    Reduce to Single Value
  - array_sum
    
    Sum of Values
  - array_product
    
    Product of Values
  - array_rand
    
    Random Key from Array
  - shuffle
    
    Randomize Array Order
  - range
    
    Create Array of Range
  - array_fill
    
    Fill Array with Values
  - array_fill_keys
    
    Fill with Keys
  - array_pad
    
    Pad Array to Size
  - array_chunk
    
    Split into Chunks
- Sorting Functions
  - sort
    
    Sort Ascending
  - rsort
    
    Sort Descending
  - asort
    
    Sort Ascending Keep Keys
  - arsort
    
    Sort Descending Keep Keys
  - ksort
    
    Sort by Keys Ascending
  - krsort
    
    Sort by Keys Descending
  - usort
    
    Sort by User Function
  - uasort
    
    Sort Values User Keep Keys
  - uksort
    
    Sort Keys User Function
  - natsort
    
    Natural Order Sort
  - natcasesort
    
    Case Insensitive Natural Sort
- Array Destructuring
  - list Function
    
    Assign Values to Variables
  - list Example
    
    $list a b c
  - Short Syntax
    
    Brackets Assignment
  - Short Example
    
    a b c equals array
  - Skip Values
    
    Comma Without Variable
  - Associative Array
    
    Square Brackets with Keys
  - Nested
    
    Destructure Nested Arrays
- Spread Operator
  - Array Unpacking
    
    Three Dots Unpack
  - Example
    
    array merge with spread
  - String Keys
    
    Works with String Keys PHP 8.1
  - Duplicate Keys
    
    Last Key Overwrites
PHP Strings
- String Creation
  - Single Quotes
    
    Literal String
  - Double Quotes
    
    Parses Variables
  - Heredoc Syntax
    
    Multi-line String
  - Nowdoc Syntax
    
    No Parsing Heredoc
- String Functions
  - strlen
    
    Get String Length
  - str_word_count
    
    Count Words
  - strrev
    
    Reverse String
  - strpos
    
    Find Substring Position
  - stripos
    
    Case Insensitive strpos
  - strrpos
    
    Find Last Position
  - strripos
    
    Case Insensitive Last
  - substr
    
    Extract Substring
  - substr_replace
    
    Replace Substring
  - str_replace
    
    Replace All Occurrences
  - str_ireplace
    
    Case Insensitive Replace
  - str_repeat
    
    Repeat String
  - str_pad
    
    Pad String to Length
  - trim
    
    Strip Whitespace Both Ends
  - ltrim
    
    Strip Left Whitespace
  - rtrim
    
    Strip Right Whitespace
  - explode
    
    Split String into Array
  - implode
    
    Join Array into String
  - join
    
    Alias of implode
  - strtolower
    
    Convert to Lowercase
  - strtoupper
    
    Convert to Uppercase
  - ucfirst
    
    Uppercase First Character
  - ucwords
    
    Uppercase Each Word First
  - lcfirst
    
    Lowercase First Character
  - htmlspecialchars
    
    Convert Special Chars to Entities
  - htmlspecialchars_decode
    
    Convert Entities to Chars
  - htmlentities
    
    Convert All to Entities
  - html_entity_decode
    
    Convert Entities to Chars
  - strip_tags
    
    Remove HTML PHP Tags
  - addslashes
    
    Quote String with Slashes
  - stripslashes
    
    Unquote Quoted String
  - md5
    
    Calculate MD5 Hash
  - sha1
    
    Calculate SHA1 Hash
  - hash
    
    Hash String with Algorithm
  - base64_encode
    
    Encode with Base64
  - base64_decode
    
    Decode Base64 String
  - urlencode
    
    URL Encode String
  - urldecode
    
    Decode URL Encoded String
  - rawurlencode
    
    URL Encode RFC 3986
  - rawurldecode
    
    Decode RFC 3986 URL
  - json_encode
    
    Convert to JSON String
  - json_decode
    
    Convert JSON to Variable
  - serialize
    
    Convert Value to String
  - unserialize
    
    Restore Serialized String
  - parse_str
    
    Parse Query String
  - http_build_query
    
    Build Query String
- printf Functions
  - printf
    
    Formatted Output
  - sprintf
    
    Return Formatted String
  - sscanf
    
    Parse Formatted Input
  - vprintf
    
    Output with Array Arguments
  - vsprintf
    
    Return with Array Arguments
- String Comparison
  - strcmp
    
    Binary Safe Compare
  - strcasecmp
    
    Case Insensitive Compare
  - strncmp
    
    Compare First N Characters
  - strncasecmp
    
    Case Insensitive N Compare
  - strnatcmp
    
    Natural Order Compare
  - strnatcasecmp
    
    Natural Case Insensitive
  - similar_text
    
    Calculate Similarity
  - levenshtein
    
    Calculate Levenshtein Distance
- String Search
  - strstr
    
    Find First Occurrence
  - stristr
    
    Case Insensitive strstr
  - strchr
    
    Alias of strstr
  - strrchr
    
    Find Last Occurrence
  - strpbrk
    
    Search for Any Character
- String Tokenization
  - strtok
    
    Tokenize String
  - Example
    
    strtok with Multiple Tokens
- Regular Expressions
  - preg_match
    
    Perform Regex Match
  - preg_match_all
    
    Perform Global Match
  - preg_replace
    
    Search Replace Regex
  - preg_split
    
    Split by Regex
  - preg_grep
    
    Filter Array by Regex
  - preg_quote
    
    Escape Regex Characters
PHP Superglobals
- $_GET
  - Definition
    
    HTTP GET Parameters
  - Usage
    
    Retrieve Query String
  - Example
    
    Get name from URL
  - Security
    
    Validate and Sanitize
- $_POST
  - Definition
    
    HTTP POST Parameters
  - Usage
    
    Retrieve Form Data
  - Example
    
    Get username from form
  - Security
    
    Validate and Sanitize
- $_POST vs GET
  - POST for Sensitive Data
    
    Hidden from URL
  - GET for Search
    
    Visible in URL
- $_REQUEST
  - Definition
    
    GET POST COOKIE Combined
  - Usage
    
    Request Data Any Method
  - Caution
    
    Prefer Specific Variables
- $_SERVER
  - Definition
    
    Server Environment Variables
  - HTTP_USER_AGENT
    
    Browser Information
  - REMOTE_ADDR
    
    Client IP Address
  - REQUEST_METHOD
    
    HTTP Method GET POST
  - REQUEST_URI
    
    Requested URL Path
  - QUERY_STRING
    
    Query String Part
  - SCRIPT_NAME
    
    Script Path
  - PHP_SELF
    
    Current Script Filename
  - SERVER_NAME
    
    Server Hostname
  - SERVER_ADDR
    
    Server IP Address
  - SERVER_PORT
    
    Server Port Number
  - HTTP_REFERER
    
    Previous Page URL
  - HTTPS
    
    Check if HTTPS Enabled
  - HTTP_HOST
    
    Host Header Value
  - DOCUMENT_ROOT
    
    Web Root Directory
- $_FILES
  - Definition
    
    Uploaded Files Array
  - name
    
    Original File Name
  - type
    
    File MIME Type
  - tmp_name
    
    Temporary File Path
  - error
    
    Upload Error Code
  - size
    
    File Size Bytes
- $_COOKIE
  - Definition
    
    HTTP Cookies Array
  - Usage
    
    Retrieve Cookie Values
  - Example
    
    Get user preference
- $_SESSION
  - Definition
    
    Session Variables Array
  - Usage
    
    Store User Data
  - Example
    
    Store user ID
  - Start Required
    
    session_start First
- $GLOBALS
  - Definition
    
    All Global Variables
  - Usage
    
    Access Anywhere
  - Example
    
    GLOBALS var name
- $_ENV
  - Definition
    
    Environment Variables
  - Usage
    
    Access System Environment
PHP Forms
- Form Handling
  - GET Method
    
    Send Data in URL
  - POST Method
    
    Send Data in Body
  - action Attribute
    
    Form Submission URL
  - name Attribute
    
    Input Field Identifier
  - method Attribute
    
    GET or POST
  - enctype Attribute
    
    Multipart for Files
- Form Validation
  - Required Field
    
    Check Not Empty
  - Email Validation
    
    Validate Format
  - Number Validation
    
    Check Numeric
  - String Length
    
    Min Max Characters
  - Pattern Matching
    
    Regex Validation
  - URL Validation
    
    Valid URL Format
  - Date Validation
    
    Check Valid Date
  - File Validation
    
    Check Type Size
  - Confirm Password
    
    Check Match
  - Checkbox Validation
    
    At Least One
  - Select Validation
    
    Option Selected
- Form Security
  - htmlspecialchars
    
    Prevent XSS Attacks
  - strip_tags
    
    Remove HTML Tags
  - filter_var
    
    Validate Sanitize Data
  - Prepared Statements
    
    Prevent SQL Injection
  - CSRF Token
    
    Prevent Cross Site Request
  - CSRF Generation
    
    Unique Token per Session
  - CSRF Validation
    
    Verify Token on Submit
  - CAPTCHA
    
    Prevent Bot Submissions
  - reCAPTCHA
    
    Google CAPTCHA Integration
  - Honeypot
    
    Hidden Field Trap Bots
  - Rate Limiting
    
    Prevent Brute Force
  - Input Sanitization
    
    Remove Dangerous Characters
  - Output Escaping
    
    Escape Before Display
- Sticky Forms
  - Remember Values
    
    Keep After Submission
  - Select Dropdown
    
    Preselect Saved Value
  - Checkbox
    
    Remember Checked State
  - Radio Button
    
    Preserve Selected Option
- File Upload
  - Form Enctype
    
    multipart form data Required
  - max_file_size
    
    Hidden Field Limit
  - Upload Directory
    
    Destination Permissions
  - move_uploaded_file
    
    Safe Move from Temp
  - is_uploaded_file
    
    Check Valid Upload
  - File Type Validation
    
    Check MIME Type
  - File Extension
    
    Check Extension Whitelist
  - Image Validation
    
    getimagesize Check
  - File Size Validation
    
    Check Max Size
  - Secure Filename
    
    Remove Special Characters
  - Unique Filename
    
    uniqid or Timestamp
  - Error UPLOAD_ERR_OK
    
    No Error
  - Error UPLOAD_ERR_INI_SIZE
    
    Exceeds Max Size
  - Error UPLOAD_ERR_FORM_SIZE
    
    Exceeds Form Limit
  - Error UPLOAD_ERR_PARTIAL
    
    Partial Upload
  - Error UPLOAD_ERR_NO_FILE
    
    No File Uploaded
  - Error UPLOAD_ERR_NO_TMP_DIR
    
    Missing Temp Folder
  - Error UPLOAD_ERR_CANT_WRITE
    
    Write Failed
  - Error UPLOAD_ERR_EXTENSION
    
    Extension Stopped Upload
  - Multiple File Upload
    
    Array Syntax for Files
  - Image Resize
    
    GD Library Thumbnail
  - File Download
    
    Force Download Headers
PHP Sessions
- Session Introduction
  - What is Session
    
    Server Side User Storage
  - Session vs Cookie
    
    Server vs Client Storage
  - Session Lifecycle
    
    Start Use Destroy
- Session Functions
  - session_start
    
    Initialize Session
  - session_id
    
    Get Set Session ID
  - session_name
    
    Get Set Session Name
  - session_destroy
    
    Delete All Session Data
  - session_unset
    
    Free Session Variables
  - session_regenerate_id
    
    Prevent Session Fixation
  - session_status
    
    Check Session State
  - session_save_path
    
    Get Set Storage Path
- Session Security
  - Session Hijacking
    
    Use HTTPS Only
  - Session Fixation
    
    Regenerate After Login
  - Session Timeout
    
    Implement Expiry
  - Secure Cookie Flag
    
    HTTPS Only Cookie
  - HttpOnly Cookie
    
    No JavaScript Access
  - SameSite Cookie
    
    CSRF Protection
- Session Storage
  - Store User ID
    
    Authentication State
  - Store Preferences
    
    Theme Language Settings
  - Store Shopping Cart
    
    Cart Items in Session
- Session Examples
  - Login System
    
    Set Session After Auth
  - Logout System
    
    Destroy Session on Logout
  - User Dashboard
    
    Check Session for Access
PHP Cookies
- Cookie Introduction
  - What is Cookie
    
    Client Side Storage
- Cookie Attributes
  - name
    
    Identifier
  - value
    
    Stored Data
  - expires
    
    Expiry Timestamp
  - path
    
    Available Path
  - domain
    
    Available Domain
  - secure
    
    HTTPS Only
  - httponly
    
    No JavaScript Access
  - samesite
    
    Strict Lax None
- Cookie Functions
  - setcookie
    
    Send Cookie to Browser
  - setrawcookie
    
    Send Without URL Encoding
  - header Cookie
    
    Alternative Set-Cookie
- Cookie Examples
  - Remember Me
    
    Long Term Login
  - User Preferences
    
    Store Theme Language
  - Analytics
    
    Track User Visits
- Cookie Security
  - Encrypt Cookie Data
    
    Sensitive Information
PHP File Handling
- File Open
  - fopen
    
    Open File or URL
- File Open Mode
- File Read
  - fread
    
    Read Bytes from File
  - fgets
    
    Read Line from File
  - fgetc
    
    Read Single Character
  - file
    
    Read Entire File to Array
  - file_get_contents
    
    Read File to String
- File Write
  - fwrite
    
    Write String to File
  - fputs
    
    Alias of fwrite
  - file_put_contents
    
    Write String to File
- File Close
  - fclose
    
    Close File Pointer
- File End
  - feof
    
    Check End of File
- File Pointer
  - rewind
    
    Reset File Pointer
  - ftell
    
    Get Pointer Position
  - fseek
    
    Move Pointer Position
- File Info
  - filesize
    
    Get File Size
  - file_exists
    
    Check File Exists
  - is_file
    
    Check Regular File
  - is_dir
    
    Check Directory
  - is_readable
    
    Check Read Permission
  - is_writable
    
    Check Write Permission
  - filemtime
    
    Last Modified Time
  - filectime
    
    Change Time
  - fileatime
    
    Last Access Time
  - pathinfo
    
    Return Path Information
  - basename
    
    Get Filename from Path
  - dirname
    
    Get Directory from Path
  - realpath
    
    Resolve Canonical Path
- File Operations
  - copy
    
    Copy File
  - rename
    
    Move or Rename
  - unlink
    
    Delete File
  - chmod
    
    Change Permissions
  - chown
    
    Change Owner
  - chgrp
    
    Change Group
- Directory Operations
  - mkdir
    
    Create Directory
  - rmdir
    
    Remove Directory
  - opendir
    
    Open Directory Handle
  - readdir
    
    Read Directory Entry
  - closedir
    
    Close Directory Handle
  - scandir
    
    List Files in Directory
  - glob
    
    Find Paths Matching Pattern
- CSV Handling
  - fgetcsv
    
    Read CSV Line
  - fputcsv
    
    Write CSV Line
  - str_getcsv
    
    Parse CSV String
- JSON File
  - json_encode file
    
    Write JSON to File
  - file_get_contents json_decode
    
    Read JSON from File
PHP Date & Time
- Date Functions
  - date
    
    Format Current Time
  - time
    
    Unix Timestamp
  - mktime
    
    Timestamp from Date
  - gmmktime
    
    GMT Timestamp
  - strtotime
    
    Parse English to Timestamp
  - getdate
    
    Get Date Array
  - gettimeofday
    
    Get Current Time
  - checkdate
    
    Validate Gregorian Date
- Date Format
  - d
    
    Day 01 to 31
    
    3 Letter Weekday
  - m
    
    Month 01 to 12
    
    3 Letter Month
  - Y
    
    Year 4 Digits
    
    Year 2 Digits
  - H
    
    Hour 00 to 23
    
    Hour 01 to 12
  - i
    
    Minutes 00 to 59
  - s
    
    Seconds 00 to 59
  - a
    
    am or pm
  - l
    
    Full Weekday Name
  - F
    
    Full Month Name
- DateTime Class
  - DateTime Object
    
    OOP Date Handling
  - __construct
    
    Create DateTime Object
  - format
    
    Format DateTime
  - modify
    
    Modify with String
  - add
    
    Add DateInterval
  - sub
    
    Subtract DateInterval
  - diff
    
    Calculate Difference
  - setTimezone
    
    Change Timezone
  - getTimezone
    
    Get Current Timezone
  - setDate
    
    Set Date Values
  - setTime
    
    Set Time Values
  - createFromFormat
    
    Parse Custom Format
  - getTimestamp
    
    Get Unix Timestamp
  - setTimestamp
    
    Set from Timestamp
- DateInterval
  - DateInterval Class
    
    Time Interval
  - format
    
    Format Interval
  - createFromDateString
    
    Create from String
- DatePeriod
  - DatePeriod Class
    
    Iterate Date Range
  - Constructor
    
    Start End Interval
  - Recurring Dates
    
    Generate Recurring Dates
- DateTimeZone
  - DateTimeZone Class
    
    Timezone Handling
  - listIdentifiers
    
    List All Timezones
  - getOffset
    
    Get Timezone Offset
- Timezone Setting
  - date_default_timezone_set
    
    Set Default Timezone
  - date_default_timezone_get
    
    Get Default Timezone
- Time Calculations
  - Age Calculator
    
    Diff from Birthdate
  - Days Between Dates
    
    Using diff Method
  - Add Days
    
    modify plus 1 day
PHP Regular Expressions
- PREG Functions
  - preg_match
    
    Perform Regex Match
  - preg_match_all
    
    Perform Global Match
  - preg_replace
    
    Search Replace Regex
  - preg_replace_callback
    
    Replace with Callback
  - preg_split
    
    Split String by Pattern
  - preg_grep
    
    Filter Array by Pattern
  - preg_quote
    
    Escape Regex Characters
  - preg_last_error
    
    Get Last Regex Error
- Pattern Delimiters
  - Forward Slash
    
    / Delimiter
  - Hash Symbol
    
    # Delimiter
  - Tilde
    
    ~ Delimiter
- Metacharacters
  - Dot
    
    Any Single Character
  - Caret
    
    Start of String
  - Dollar
    
    End of String
  - Asterisk
    
    Zero or More Times
  - Plus
    
    One or More Times
  - Question Mark
    
    Zero or One Time
  - Curly Braces
    
    Exact Number of Times
- Character Classes
  - Square Brackets
    
    Any Character in Set
  - Negated Class
    
    Caret Inside Brackets
  - Range Hyphen
    
    A to Z Range
- Shortcut Classes
  - Digits
    
    d Character
  - Non Digits
    
    D Character
  - Word Characters
    
    w Character
  - Non Word
    
    W Character
  - Whitespace
    
    s Character
  - Non Whitespace
    
    S Character
- Modifiers
  - i Modifier
    
    Case Insensitive
  - m Modifier
    
    Multiline Mode
  - s Modifier
    
    Dot Matches Newline
  - x Modifier
    
    Ignore Whitespace
  - u Modifier
    
    UTF-8 Mode
- Groups
  - Capturing Group
    
    Parentheses Capture
  - Non Capturing Group
    
    (?: Pattern)
  - Named Group
    
    P Name Pattern
  - Backreference
    
    Number Reference
- Alternation
  - Vertical Bar
    
    OR Operator
- Lookahead
  - Positive Lookahead
    
    (?= Pattern)
  - Negative Lookahead
    
    (?! Pattern)
- Lookbehind
  - Positive Lookbehind
    
    (?<= Pattern)
  - Negative Lookbehind
    
    (?<! Pattern)
- Email Validation
  - Email Regex Pattern
    
    Validate Email Format
- URL Validation
  - URL Regex Pattern
    
    Validate URL Format
- Phone Validation
  - Phone Regex Pattern
    
    Validate Phone Number
- IP Validation
  - IP Address Regex
    
    Validate IPv4 IPv6
- Username Validation
  - Username Regex
    
    Alphanumeric Underscore
- Password Validation
  - Password Strength Regex
    
    Complex Password Pattern
PHP OOP
- Classes
  - class Keyword
    
    Define Class Blueprint
  - Class Naming
    
    PascalCase Convention
  - Example Class
    
    User Class Definition
- Objects
  - new Keyword
    
    Create Object Instance
  - Object Variable
    
    $object = new Class
  - Multiple Objects
    
    Multiple Instances Possible
- Properties
  - Property Declaration
    
    public protected private
  - Property Types
    
    Type Declaration PHP 7.4
  - Property Initialization
    
    Default Values
  - Nullable Properties
    
    Question Mark Type
  - Property Access
    
    Arrow Operator
  - Property Assignment
    
    object property value
- Methods
  - Method Declaration
    
    public protected private
  - Method Return Type
    
    colon type Declaration
  - Method Parameters
    
    Pass Values to Methods
  - Method Call
    
    object method name
  - Method Chaining
    
    return this for Fluent
- $this Keyword
  - $this Variable
    
    Current Object Reference
- $this Usage
  - Access Properties
    
    $this property
  - Call Methods
    
    $this method
- Constructor
  - __construct Method
    
    Automatically Called
  - Constructor Parameters
    
    Pass Initial Values
  - Constructor Promotion
    
    PHP 8 Declare Properties
  - Parent Constructor
    
    parent construct Call
- Destructor
  - __destruct Method
    
    Automatically Called
  - Use Cases
    
    Close Database Connections
    
    Free Resources
- Inheritance
  - extends Keyword
    
    Child Extends Parent
  - Parent Class
    
    Base Class Definition
  - Child Class
    
    Derived Class Definition
  - Method Override
    
    Child Redefines Parent Method
  - parent Keyword
    
    Access Parent Method
  - final Keyword
    
    Prevent Method Override
  - final Class
    
    Prevent Class Extension
  - Multiple Inheritance
    
    Not Allowed in PHP
- Visibility
  - public Keyword
    
    Access from Anywhere
  - protected Keyword
    
    Access Inside Class and Child
  - private Keyword
    
    Access Only Inside Class
  - Property Best Practices
    
    Private by Default
- Getters and Setters
  - Getter Method
    
    Return Private Property
  - Setter Method
    
    Set Private Property
  - Validation in Setter
    
    Validate Before Set
  - Readonly Property
    
    Only Getter No Setter
- Abstract Classes
  - abstract Keyword
    
    Cannot Instantiate
  - Abstract Method
    
    No Implementation Only Declaration
  - Concrete Method
    
    Full Implementation Allowed
  - Child Implementation
    
    Child Must Implement Abstract Methods
- Interfaces
  - interface Keyword
    
    Define Contract
  - implements Keyword
    
    Class Implements Interface
  - Multiple Interfaces
    
    Implement Multiple Interfaces
  - Interface Inheritance
    
    Interface Extends Interface
  - Interface Constants
    
    Constants in Interface
  - Abstract vs Interface
    
    When to Use Which
- Traits
  - trait Keyword
    
    Code Reuse Mechanism
  - use Keyword
    
    Import Trait into Class
  - Multiple Traits
    
    Use Multiple Traits
  - Conflict Resolution
    
    insteadof Operator
  - Alias Method
    
    as Operator Change Visibility
  - Trait Composition
    
    Trait Can Use Trait
  - Properties in Traits
    
    Traits Can Declare Properties
  - Abstract Methods
    
    Traits Can Require Methods
- Static Methods
  - static Keyword
    
    Call on Class Not Object
    
    Late Binding
  - Method Call
    
    ClassName method
  - self Keyword
    
    Early Binding
  - parent Keyword
    
    Call Parent Static
- Static Properties
  - static Property
    
    Shared Across Instances
  - Access Syntax
    
    ClassName dollar property
  - self Access
    
    self dollar property
  - static Access
    
    static dollar property
- Late Static Binding
  - static Resolution
    
    Runtime Class Name
  - get_called_class
    
    Get Late Static Class
- Magic Methods
  - __construct
    
    Object Constructor
  - __destruct
    
    Object Destructor
  - __get
    
    Access Undefined Property
  - __set
    
    Set Undefined Property
  - __isset
    
    Check Undefined Property
  - __unset
    
    Unset Undefined Property
  - __call
    
    Call Undefined Method
  - __callStatic
    
    Call Undefined Static Method
  - __toString
    
    String Representation
  - __invoke
    
    Object as Function
  - __clone
    
    Called on Clone
  - __sleep
    
    Serialize Properties
  - __wakeup
    
    Unserialize Reinitialize
  - __serialize
    
    Custom Serialization PHP 7.4
  - __unserialize
    
    Custom Unserialize PHP 7.4
  - __debugInfo
    
    Var Dump Custom Output
  - __set_state
    
    Var Export Handler
- Object Cloning
  - clone Keyword
    
    Create Object Copy
  - Shallow Copy
    
    Default Clone Behavior
  - Deep Copy
    
    Manual Clone Nested Objects
  - __clone Method
    
    Customize Clone Behavior
- Object Comparison
  - Equal Operator
    
    Compare Property Values
  - Identical Operator
    
    Compare Object Identity
- Object Serialization
  - serialize Function
    
    Convert Object to String
  - unserialize Function
    
    Restore Object from String
  - Serializable Interface
    
    Deprecated in PHP 8
- Namespaces
  - namespace Keyword
    
    Define Namespace
  - use Keyword
    
    Import Namespace Class
  - as Keyword
    
    Namespace Alias
  - Fully Qualified Name
    
    Backslash Global Namespace
  - Subnamespaces
    
    Nested Namespace Structure
  - Multiple Namespaces
    
    Same File Multiple Namespaces
  - Bracketed Syntax
    
    Namespace with Braces
  - PSR-4
    
    Autoloading Standard
- Anonymous Classes
  - new class
    
    Create One Off Object
  - Constructor
    
    Can Have Constructor
  - Extend Class
    
    Can Extend Other Classes
  - Implement Interface
    
    Can Implement Interfaces
  - Use Cases
    
    Simple Mock Objects
- Iterators
  - Iterator Interface
    
    Implement Custom Iteration
  - IteratorAggregate
    
    Return External Iterator
  - ArrayIterator
    
    Iterate Over Arrays
  - ArrayObject
    
    Treat Array as Object
- Generators
  - yield Keyword
    
    Generate Values On Demand
  - yield from
    
    Delegate Generation
  - Generator Object
    
    Send Throw GetReturn
  - Memory Efficiency
    
    Generate Large Datasets
- Reflection
  - ReflectionClass
    
    Inspect Class Information
  - ReflectionMethod
    
    Inspect Method Information
  - ReflectionProperty
    
    Inspect Property Information
  - ReflectionParameter
    
    Inspect Parameter Information
  - ReflectionAttribute
    
    PHP 8 Attribute Reflection
  - Use Cases
    
    Dependency Injection Containers
- Attributes
  - Attribute Syntax
    
    Hash Attribute PHP 8
  - Attribute Class
    
    Create Custom Attribute
  - Attribute Target
    
    Class Method Property Constant
  - Attribute Flags
    
    Attribute TARGET ALL
  - Repeatable Attribute
    
    Allow Multiple Same Attribute
  - Read Attributes
    
    Reflection API Access
- Enums
  - enum Keyword
    
    PHP 8.1 Enumerations
  - Basic Enum
    
    Simple Case Values
  - Backed Enum
    
    String or Int Backed Values
  - Enum Methods
    
    Enums Can Have Methods
  - Enum Static Methods
    
    Enums Have Static Methods
  - Enum Constants
    
    Enums Have Constants
  - Enum in Switch
    
    Use Enum in Switch Cases
  - Enum vs Class
    
    When to Use Enums
PHP Database
- MySQLi Introduction
  - MySQLi Extension
    
    MySQL Improved Extension
- MySQLi Connection
  - Procedural Connect
    
    mysqli_connect Function
  - OOP Connect
    
    new mysqli Constructor
  - Connection Parameters
    
    Host Username Password Database
  - Error Check
    
    mysqli_connect_error
  - Set Charset
    
    mysqli_set_charset UTF-8
  - Close Connection
    
    mysqli_close
- MySQLi Query
  - Simple Query
    
    mysqli_query Function
  - SELECT Query
    
    Fetch Data from Database
  - INSERT Query
    
    Add New Records
  - UPDATE Query
    
    Modify Existing Records
  - DELETE Query
    
    Remove Records
- MySQLi Fetch
  - mysqli_fetch_assoc
    
    Associative Array Fetch
  - mysqli_fetch_object
    
    Object Fetch
  - mysqli_fetch_array
    
    Both Types Fetch
  - mysqli_fetch_all
    
    Fetch All Rows
  - mysqli_num_rows
    
    Get Row Count
  - mysqli_affected_rows
    
    Affected Row Count
  - mysqli_insert_id
    
    Last Insert ID
- MySQLi Prepared
  - Prepared Statement Benefits
    
    Prevent SQL Injection
  - prepare Method
    
    Prepare SQL Statement
  - bind_param
    
    Bind Parameters
  - Parameter Types
    
    s i d b Strings Integer Double Blob
  - execute Method
    
    Execute Statement
  - store_result
    
    Store Result Set
  - bind_result
    
    Bind Result Columns
  - fetch Method
    
    Fetch Result Row
  - get_result
    
    Get Result Set Object
  - INSERT with Prepared
    
    Secure Insert Operation
  - UPDATE with Prepared
    
    Secure Update Operation
  - DELETE with Prepared
    
    Secure Delete Operation
  - SELECT with Prepared
    
    Secure Select Operation
- MySQLi Multi Query
  - multi_query
    
    Execute Multiple Queries
  - next_result
    
    Move to Next Result Set
- MySQLi Transactions
  - autocommit
    
    Disable Auto Commit
  - begin_transaction
    
    Start Transaction
  - commit
    
    Save All Changes
  - rollback
    
    Revert All Changes
  - Example
    
    Bank Money Transfer
- MySQLi Error
  - mysqli_error
    
    Get Last Error Message
  - mysqli_errno
    
    Get Last Error Code
  - mysqli_sqlstate
    
    Get SQL State Error
- MySQLi Escape
  - mysqli_real_escape_string
    
    Escape Special Characters
- PDO Introduction
  - PDO Extension
    
    PHP Data Objects
- PDO Benefits
  - Multiple Databases
    
    Supports 12 Drivers
- PDO vs MySQLi
  - PDO More Databases
    
    MySQLi MySQL Only
- PDO Connection
  - PDO Constructor
    
    Create PDO Instance
  - DSN String
    
    Data Source Name Format
  - MySQL DSN
    
    mysql host dbname
  - Connection Options
    
    Set PDO Attributes
  - Error Mode
    
    ERRMODE EXCEPTION
  - Connection Check
    
    Try Catch for Errors
  - Close Connection
    
    Set PDO to null
- PDO Query
  - query Method
    
    Single Query Execution
  - exec Method
    
    Returns Affected Rows
- PDO Fetch
  - PDO FETCH_ASSOC
    
    Associative Array Fetch
  - PDO FETCH_OBJ
    
    Object Fetch
  - PDO FETCH_BOTH
    
    Both Associative Indexed
  - PDO FETCH_CLASS
    
    Fetch into Class Instance
  - fetch Method
    
    Get Single Row
  - fetchAll Method
    
    Get All Rows
  - fetchColumn
    
    Get Single Column
  - rowCount
    
    Get Number of Rows
- PDO Prepared
  - prepare Method
    
    Prepare SQL Statement
  - bindParam
    
    Bind by Reference
  - bindValue
    
    Bind by Value
  - execute Method
    
    Execute Statement
  - Named Placeholders
    
    Colon Name Parameter Style
  - Question Mark Placeholders
    
    Positional Parameters
  - INSERT Prepared
    
    Secure Insert with PDO
  - UPDATE Prepared
    
    Secure Update with PDO
  - DELETE Prepared
    
    Secure Delete with PDO
  - SELECT Prepared
    
    Secure Select with PDO
  - Reuse Statement
    
    Execute Multiple Times
- PDO Transactions
  - beginTransaction
    
    Start Transaction PDO
  - commit
    
    Commit Transaction PDO
  - rollBack
    
    Rollback Transaction PDO
  - inTransaction
    
    Check if Active
- PDO Error
  - errorInfo
    
    Get Error Information Array
  - errorCode
    
    Get Error Code
  - PDOException
    
    Catch PDO Exceptions
- PDO Attributes
  - setAttribute
    
    Set PDO Attribute
  - getAttribute
    
    Get PDO Attribute
  - ATTR ERRMODE
    
    Error Reporting Mode
  - ATTR DEFAULT FETCH MODE
    
    Default Fetch Style
  - ATTR EMULATE PREPARES
    
    Emulated Prepares
- PDO Last ID
  - lastInsertId
    
    Get Last Inserted ID
- PDO Metadata
  - getColumnMeta
    
    Get Column Metadata
- PDO Drivers
  - getAvailableDrivers
    
    List Available Drivers
PHP Error Handling
- Error Types
  - PHP Parse Error
    
    Syntax Error Script Won't Run
  - PHP Fatal Error
    
    Script Execution Stops
  - PHP Warning
    
    Continues but Warning Shown
  - PHP Notice
    
    Minor Issue Continues
  - PHP Deprecated
    
    Feature Will Be Removed
- Error Reporting
  - error_reporting
    
    Set Error Level
  - display_errors
    
    Show Errors in Browser
  - log_errors
    
    Log Errors to File
- Error Levels
  - E_ALL
    
    All Errors and Warnings
  - E_ERROR
    
    Fatal Runtime Errors
  - E_WARNING
    
    Runtime Warnings
  - E_PARSE
    
    Compile Time Parse Errors
  - E_NOTICE
    
    Runtime Notices
  - E_DEPRECATED
    
    Deprecated Code Warnings
  - E_STRICT
    
    Strict Standards
- Custom Handler
  - set_error_handler
    
    User Defined Error Handler
  - Handler Parameters
    
    errno errstr errfile errline
  - restore_error_handler
    
    Restore Previous Handler
- Exception Handling
  - try Block
    
    Code That May Throw Exception
  - catch Block
    
    Handle Exception
  - finally Block
    
    Always Executes
- Exception Class
  - Throwable Interface
    
    Base Exception Interface
  - Exception Class
    
    Base Exception Class
  - throw Keyword
    
    Throw Exception Manually
- Exception Methods
  - getMessage
    
    Get Exception Message
  - getCode
    
    Get Exception Code
  - getFile
    
    Get File Where Thrown
  - getLine
    
    Get Line Where Thrown
  - getTrace
    
    Get Stack Trace Array
  - getTraceAsString
    
    Get Stack Trace String
- Custom Exceptions
  - Extend Exception
    
    Create Custom Exception Types
  - Multiple Types
    
    Handle Different Exceptions
  - Exception Hierarchies
    
    Parent Child Exceptions
- Multiple Catch
  - Catch Multiple
    
    Different Exception Types
  - Catch All
    
    Catch Throwable Interface
- Rethrow
  - throw in catch
    
    Rethrow with Different Type
- Exception Chaining
  - Previous Exception
    
    Pass Previous to Constructor
- Global Handler
  - set_exception_handler
    
    Uncaught Exception Handler
  - restore_exception_handler
    
    Restore Previous Handler
- Error to Exception
  - ErrorException Class
    
    Convert Errors to Exceptions
  - Handler Throw
    
    Throw ErrorException in Handler
- Production Practices
  - Error Logging
    
    Log Don't Display
  - Custom Error Page
    
    User Friendly Messages
  - Error Monitoring
    
    Sentry Bugsnag Integration
PHP Security
- SQL Injection
  - Overview
    
    What is SQL Injection
  - Vulnerable Code
    
    Direct Variable in Query
  - Prevention Method
    
    Use Prepared Statements
  - PDO Prevention
    
    Use PDO with Prepares
  - MySQLi Prevention
    
    Use MySQLi Prepared
  - Escape Function
    
    mysqli_real_escape_string Usage
  - Validation Method
    
    Validate All User Inputs
  - Stored Procedure
    
    Safe Stored Procedure Usage
- XSS Prevention
  - Overview
    
    What is Cross Site Scripting
  - htmlspecialchars
    
    Convert Special Characters
  - ENT_QUOTES Flag
    
    Convert Both Quotes
  - strip_tags Function
    
    Remove HTML PHP Tags
  - filter_var Sanitize
    
    Sanitize String Filter
  - Output Escaping
    
    Escape Before Display
  - CSP Header
    
    Content Security Policy
  - Cookie Flag
    
    HttpOnly Cookie Prevention
- CSRF Prevention
  - Overview
    
    What is CSRF Attack
  - Token Generation
    
    bin2hex random_bytes
  - Store Token
    
    Store in Session
  - Form Field
    
    Add Hidden Input Field
  - Validate Token
    
    Compare with Session
  - hash_equals Function
    
    Timing Safe Comparison
  - SameSite Cookie
    
    Cookie SameSite Strict
  - Double Submit
    
    Alternative CSRF Protection
  - Referer Check
    
    Verify HTTP Referer Header
- Password Hashing
  - password_hash Function
    
    Create Secure Hash
  - password_verify Function
    
    Verify Password
  - password_needs_rehash
    
    Check Rehash Needed
  - password_get_info
    
    Get Hash Algorithm Info
  - PASSWORD_DEFAULT
    
    Default BCrypt Algorithm
  - PASSWORD_BCRYPT
    
    BCrypt Algorithm
  - PASSWORD_ARGON2I
    
    Argon2i Algorithm
  - PASSWORD_ARGON2ID
    
    Argon2id Algorithm
  - BCrypt Cost
    
    Set Cost Parameter
  - Argon2 Memory
    
    Memory Cost Parameter
  - Argon2 Time
    
    Time Cost Parameter
  - Argon2 Threads
    
    Threads Parameter
  - Hash Length
    
    BCrypt 60 Characters
  - Best Practice
    
    Always Hash Passwords
- Input Validation
  - filter_var Function
    
    Validate and Sanitize
  - FILTER_VALIDATE_EMAIL
    
    Validate Email Format
  - FILTER_VALIDATE_URL
    
    Validate URL Format
  - FILTER_VALIDATE_IP
    
    Validate IP Address
  - FILTER_VALIDATE_INT
    
    Validate Integer
  - FILTER_VALIDATE_BOOLEAN
    
    Validate Boolean
  - FILTER_VALIDATE_FLOAT
    
    Validate Float
  - FILTER_VALIDATE_REGEXP
    
    Validate with Regex
  - FILTER_SANITIZE_EMAIL
    
    Sanitize Email String
  - FILTER_SANITIZE_URL
    
    Sanitize URL String
  - FILTER_SANITIZE_NUMBER_INT
    
    Remove Non Numeric
  - FILTER_SANITIZE_NUMBER_FLOAT
    
    Remove Non Float
  - FILTER_SANITIZE_SPECIAL_CHARS
    
    HTML Encode String
  - filter_input Function
    
    Filter from Superglobal
  - filter_input_array
    
    Filter Multiple Inputs
  - Validation vs Sanitization
    
    Reject vs Clean
- File Upload Security
  - Type Validation
    
    Check MIME Type
  - finfo_file Function
    
    Get Real MIME Type
  - Extension Whitelist
    
    Allow Specific Extensions
  - Image Validation
    
    getimagesize Function
  - Size Limit
    
    Check Maximum File Size
  - Secure Filename
    
    preg_replace Dangerous Chars
  - Unique Name
    
    uniqid Generation
  - Storage Location
    
    Outside Webroot Directory
  - File Permissions
    
    chmod 644 for Files
  - Serve File
    
    Readfile for Access Control
  - Malware Scan
    
    ClamAV Integration
- Session Security
  - Session Hijacking
    
    Use HTTPS Only
  - Regenerate ID
    
    session_regenerate_id After Login
  - Session Timeout
    
    Implement Idle Timeout
  - Secure Cookie Flag
    
    Set Secure Flag
  - HttpOnly Cookie Flag
    
    Set HttpOnly Flag
  - SameSite Cookie Flag
    
    Set SameSite Flag
  - Disable Trans ID
    
    Prevent URL Session ID
  - Database Storage
    
    Use Database for Sessions
  - Validation Method
    
    Check User Agent IP
- HTTPS
  - Force HTTPS
    
    Redirect HTTP to HTTPS
  - HSTS Header
    
    Strict Transport Security
  - Secure Flag Cookies
    
    Set-Cookie Secure Flag
  - Proxy Support
    
    HTTP X Forwarded Proto
- HTTP Headers
  - X-Frame-Options
    
    Prevent Clickjacking
  - X-Content-Type-Options
    
    Prevent MIME Sniffing
  - Referrer-Policy
    
    Control Referrer Information
  - Permissions-Policy
    
    Browser Feature Restrictions
- CSP Header
  - Content-Security-Policy
    
    Whitelist Resource Sources
  - default-src
    
    Fallback Source Policy
  - script-src
    
    Allowed Script Sources
  - style-src
    
    Allowed Style Sources
  - img-src
    
    Allowed Image Sources
  - connect-src
    
    Allowed API Endpoints
  - report-uri
    
    Report Violations URL
- CORS
  - Overview
    
    Cross Origin Resource Sharing
  - Allow Origin
    
    Access-Control-Allow-Origin Header
  - Allow Methods
    
    Access-Control-Allow-Methods Header
  - Allow Headers
    
    Access-Control-Allow-Headers Header
  - Allow Credentials
    
    Access-Control-Allow-Credentials Header
  - Preflight Request
    
    OPTIONS Method Handling
- API Security
  - Rate Limiting
    
    Prevent Brute Force
  - JWT Authentication
    
    JSON Web Tokens
  - API Keys
    
    Generate and Validate Keys
  - OAuth 2.0
    
    Third Party Authentication
  - Input Validation
    
    Validate All API Inputs
  - Output Sanitization
    
    Sanitize JSON Responses
- Environment Security
  - .env Files
    
    Store Secrets Outside Code
  - getenv Function
    
    Access Environment Variables
  - putenv Function
    
    Set Environment Variable
- Production Security
  - display_errors Off
    
    Don't Show Errors to Users
  - log_errors On
    
    Log Errors to File
  - error_log Path
    
    Set Error Log Location
  - Custom Error Page
    
    User Friendly Error Display
- SSRF Prevention
  - What is SSRF
    
    Server Side Request Forgery
  - Allowlist URLs
    
    Trusted Domain List
  - Disable Redirects
    
    Prevent Location Spoofing
  - Validate IP Address
    
    Block Internal IPs
  - cURL Options
    
    CURLOPT_REDIR_PROTOCOLS
  - Practical Example
    
    Safe URL Fetcher
- XXE Prevention
  - What is XXE
    
    XML External Entity Attack
  - libxml_disable_entity_loader
    
    Disable External Entities
  - libxml_set_external_entity_loader
    
    Disable Loading
  - DOMParser Options
    
    Disable Entity Loading
  - SimpleXML Options
    
    Safe XML Parsing
  - Practical Example
    
    Safe XML Loader
- Path Traversal
  - What is Path Traversal
    
    Directory Traversal Attack
  - realpath Validation
    
    Resolve Canonical Path
  - basename Function
    
    Extract Safe Filename
  - Path Whitelist
    
    Allowed Directories Only
  - Practical Example
    
    Safe File Reader
- Log Forging
  - What is Log Forging
    
    Injection in Log Files
  - Remove Newlines
    
    Sanitize Log Input
  - JSON Encoding
    
    Encode Special Characters
  - Practical Example
    
    Safe Logger Function
- LDAP Injection
  - What is LDAP Injection
    
    LDAP Query Attack
  - ldap_escape Function
    
    Escape LDAP Special Chars
  - Input Validation
    
    Validate Before Query
  - Practical Example
    
    Safe LDAP Search
PHP JSON
- json_encode
  - Basic Usage
    
    Convert PHP to JSON
  - PRETTY PRINT
    
    JSON_PRETTY_PRINT Flag
  - UNESCAPED UNICODE
    
    JSON_UNESCAPED_UNICODE Flag
  - UNESCAPED SLASHES
    
    JSON_UNESCAPED_SLASHES Flag
  - NUMERIC CHECK
    
    JSON_NUMERIC_CHECK Flag
  - FORCE OBJECT
    
    JSON_FORCE_OBJECT Flag
  - THROW ERROR
    
    JSON_THROW_ON_ERROR Flag
- json_decode
  - Basic Usage
    
    Convert JSON to PHP
  - Associative True
    
    Return Array Not Object
  - Depth Limit
    
    Maximum Nesting Depth
  - BigInt String
    
    JSON_BIGINT_AS_STRING Flag
- Error Constants
  - JSON_ERROR_NONE
    
    No Error Occurred
  - JSON_ERROR_DEPTH
    
    Maximum Depth Exceeded
  - JSON_ERROR_STATE_MISMATCH
    
    Invalid JSON Format
  - JSON_ERROR_CTRL_CHAR
    
    Control Character Error
  - JSON_ERROR_SYNTAX
    
    Syntax Error
  - JSON_ERROR_UTF8
    
    Malformed UTF-8 Characters
- File Handling
  - Read JSON File
    
    file_get_contents with decode
  - Write JSON File
    
    encode with file_put_contents
  - Pretty Print File
    
    Human Readable JSON Storage
- Validation
  - Validate JSON String
    
    Check decode not null
- Nested JSON
  - Complex Structures
    
    Handle Nested JSON Data
- Object Serialization
  - Serialize Objects
    
    Convert Objects to JSON
- Array Handling
  - Numeric Arrays
    
    Indexed Arrays to JSON
  - Associative Arrays
    
    Key Value to JSON
PHP XML
- SimpleXML
  - Load from File
    
    simplexml_load_file Function
  - Load from String
    
    simplexml_load_string Function
  - Access Elements
    
    Object Property Access
  - Access Attributes
    
    Attribute Array Access
  - Iterate Elements
    
    foreach Loop on SimpleXML
  - XPath Query
    
    xpath Method Query
  - Modify Elements
    
    Assign New Values
  - Add Child Element
    
    addChild Method
  - Add Attribute
    
    addAttribute Method
  - Remove Element
    
    unset on SimpleXML
  - Convert to String
    
    asXML Method
  - Namespaces
    
    Handling XML Namespaces
  - Get Children
    
    children Method
  - Get Attributes
    
    attributes Method
- DOMDocument
  - Load XML String
    
    loadXML Method
  - Load HTML String
    
    loadHTML Method
  - Load HTML File
    
    loadHTMLFile Method
  - Save XML
    
    saveXML Method
  - Save HTML
    
    saveHTML Method
  - Create Element
    
    createElement Method
  - Create Text Node
    
    createTextNode Method
  - Create Attribute
    
    createAttribute Method
  - Append Child
    
    appendChild Method
  - Insert Before
    
    insertBefore Method
  - Remove Child
    
    removeChild Method
  - Get Element ID
    
    getElementById Method
  - Get Elements Tag
    
    getElementsByTagName Method
- DOMXPath
  - Create Query
    
    DOMXPath Constructor
  - Execute Query
    
    evaluate Method
- XMLReader
  - Open File
    
    xmlreader open Method
  - Read Node
    
    xmlreader read Method
  - Get Node Type
    
    nodeType Property
  - Get Node Name
    
    name Property
  - Get Node Value
    
    value Property
- XMLWriter
  - Open Memory
    
    openMemory Method
  - Start Document
    
    startDocument Method
  - Start Element
    
    startElement Method
  - Write Element
    
    writeElement Method
  - Write Attribute
    
    writeAttribute Method
  - Write Text
    
    text Method
  - End Element
    
    endElement Method
  - End Document
    
    endDocument Method
  - Get Output
    
    outputMemory Method
PHP cURL
- cURL
  - Introduction
    
    Client URL Library
  - Initialize
    
    curl_init Function
  - Set Option
    
    curl_setopt Function
  - Execute Request
    
    curl_exec Function
  - Close Session
    
    curl_close Function
  - Get Error
    
    curl_error Function
  - Get Error Number
    
    curl_errno Function
  - Get Info
    
    curl_getinfo Function
- Options
  - CURLOPT_URL
    
    Set Request URL
  - CURLOPT_RETURNTRANSFER
    
    Return as String
  - CURLOPT_HEADER
    
    Include Headers Output
  - CURLOPT_TIMEOUT
    
    Request Timeout Seconds
  - CURLOPT_FOLLOWLOCATION
    
    Follow Redirects
  - CURLOPT_MAXREDIRS
    
    Maximum Redirects
- HTTP Methods
  - GET Request
    
    Default cURL Method
  - POST Request
    
    CURLOPT_POST Set True
  - POST Fields
    
    CURLOPT_POSTFIELDS
  - POST Array
    
    HTTP POST Form Data
  - POST JSON
    
    JSON with Content-Type
  - PUT Request
    
    CURLOPT_CUSTOMREQUEST PUT
  - DELETE Request
    
    CURLOPT_CUSTOMREQUEST DELETE
- Headers
  - HTTP Headers
    
    CURLOPT_HTTPHEADER Array
  - Content-Type
    
    application/json Header
  - Authorization
    
    Bearer Token Header
  - User Agent
    
    CURLOPT_USERAGENT
- SSL
  - SSL Verification
    
    CURLOPT_SSL_VERIFYPEER
  - Disable SSL Verify
    
    Only for Development
- Authentication
  - HTTP Basic Auth
    
    CURLOPT_USERPWD
- Proxy
  - HTTP Proxy
    
    CURLOPT_PROXY
  - Proxy Authentication
    
    CURLOPT_PROXYUSERPWD
- Cookies
  - Save Cookies
    
    CURLOPT_COOKIEJAR
  - Read Cookies
    
    CURLOPT_COOKIEFILE
- File Upload
  - Upload File
    
    CURLFile Class
- Concurrent
  - Multi Init
    
    curl_multi_init
  - Add Handle
    
    curl_multi_add_handle
  - Execute Multi
    
    curl_multi_exec
  - Select Multi
    
    curl_multi_select
  - Get Content
    
    curl_multi_getcontent
  - Remove Handle
    
    curl_multi_remove_handle
  - Close Multi
    
    curl_multi_close
- REST API
  - GET Request
    
    Fetch Data from API
  - POST Request
    
    Create Resource via API
  - PUT Request
    
    Update Resource via API
  - DELETE Request
    
    Delete Resource via API
- API Authentication
  - Bearer Token
    
    Authorization Bearer Header
  - API Key
    
    X-API-Key Header
PHP API Development
- REST API
  - Definition
    
    Representational State Transfer
- REST Methods
  - HTTP Methods
    
    GET POST PUT PATCH DELETE
- API Endpoints
  - URL Structure
    
    Resource Based URLs
- API Response
  - JSON Format
    
    JSON Response Standard
- Status Codes
  - 200 OK
    
    Success Response
  - 201 Created
    
    Resource Created
  - 400 Bad Request
    
    Client Error
  - 401 Unauthorized
    
    Authentication Required
  - 403 Forbidden
    
    Access Denied
  - 404 Not Found
    
    Resource Missing
  - 422 Unprocessable
    
    Validation Failed
  - 500 Server Error
    
    Internal Server Error
- Response Structure
  - Success Field
    
    Indicate Success Status
  - Message Field
    
    Human Readable Message
  - Data Field
    
    Response Data
  - Errors Field
    
    Validation Errors
- API Versioning
  - URL Versioning
    
    /v1/api/resource
  - Header Versioning
    
    Accept Header Version
- API Authentication
  - API Keys
    
    Simple Token Authentication
  - JWT Tokens
    
    JSON Web Token Auth
- JWT
  - Create Token
    
    Generate JWT Token
  - Validate Token
    
    Verify Token Signature
  - PHP Library
    
    firebase/php-jwt Package
- Rate Limiting
  - Implementation
    
    Throttling Requests
  - Headers
    
    X-RateLimit-Limit Header
    
    X-RateLimit-Remaining Header
    
    X-RateLimit-Reset Header
- Pagination
  - Limit Offset
    
    limit offset Parameters
  - Page Parameter
    
    page per_page Parameters
  - Response Metadata
    
    total pages next previous
- Filtering
  - Filter Parameters
    
    Filter by Field Values
- Sorting
  - Sort Parameters
    
    sort_by sort_order
- Searching
  - Search Parameter
    
    q or search Parameter
- API Documentation
  - OpenAPI Specification
    
    Swagger Documentation
- API Testing
  - Postman Tool
    
    Test API Endpoints
- CORS Handling
  - Cross Origin
    
    Handle CORS Headers
- Error Handling
  - Consistent Format
    
    Standard Error Response
- Validation
  - Request Validation
    
    Validate Input Data
- Logging
  - API Logs
    
    Log Requests and Responses
PHP Email
- mail Function
  - Basic Usage
    
    Send Simple Email
  - Parameters
    
    To Subject Message Headers
  - Headers Format
    
    From CC BCC Reply-To
  - Return Value
    
    True if Accepted
  - Additional Headers
    
    Carriage Return Line Feed
  - Plain Text Email
    
    Simple Text Email Example
  - HTML Email
    
    Content-Type text/html Header
  - HTML Images
    
    Embed Images with CID
  - Limitations
    
    May Go to Spam Folder
  - SMTP Config
    
    php.ini SMTP Settings
- PHPMailer
  - Introduction
    
    PHP Email Library
  - Installation
    
    Composer require phpmailer
  - SMTP Setup
    
    isSMTP Method
  - SMTP Host
    
    Host Property
  - SMTP Auth
    
    SMTPAuth Property
  - SMTP Username
    
    Username Property
  - SMTP Password
    
    Password Property
  - SMTP Secure
    
    SMTPSecure Property TLS SSL
  - SMTP Port
    
    Port Property 587 or 465
  - Set From
    
    setFrom Method
  - Add Recipient
    
    addAddress Method
  - Add CC
    
    addCC Method
  - Add BCC
    
    addBCC Method
  - Reply To
    
    addReplyTo Method
  - Email Subject
    
    Subject Property
  - Email Body
    
    Body Property HTML
  - Alt Body
    
    AltBody Property Plain Text
  - Add Attachment
    
    addAttachment Method
  - HTML Format
    
    isHTML Method
  - Send Email
    
    send Method
  - Error Info
    
    ErrorInfo Property
  - Gmail Setup
    
    Gmail SMTP Configuration
  - Outlook Setup
    
    Outlook SMTP Settings
  - String Attachment
    
    addStringAttachment Method
  - Embed Image
    
    addEmbeddedImage Method
- Email Validation
  - Validate Format
    
    Validate Email Address
- Email Verification
  - Send Link
    
    Send Verification Link
- Email Templates
  - HTML Design
    
    HTML Email Template
- Email Queue
  - Database Queue
    
    Bulk Email Queue
- Rate Limiting
  - Prevent Spam
    
    Email Rate Limits
- SwiftMailer
  - Alternative Library
    
    SwiftMailer Package
PHP 8 Features
- Constructor Promotion
  - Property Promotion
    
    Declare Properties in Constructor
  - Syntax
    
    public __construct public name
  - Visibility
    
    public private protected
- Named Arguments
  - Parameter Names
    
    Call with Parameter Names
  - Example
    
    array_fill start_index 0
  - Any Order
    
    Parameters Any Order
- Attributes
  - Syntax
    
    Hash Attribute Name
  - Create Class
    
    Create Attribute Class
  - Target
    
    Attribute Target Flags
  - Repeatable
    
    Allow Multiple Attributes
- Match Expression
  - Match Syntax
    
    Switch Replacement Returns Value
  - Strict Comparison
    
    Triple Equal Match
  - Default Pattern
    
    Match Default Case
  - Multiple Conditions
    
    Comma Separated Conditions
- Nullsafe Operator
  - Nullsafe Syntax
    
    Question Mark Arrow
  - Chaining
    
    user address city Chaining
- Union Types
  - Union Syntax
    
    int string float
  - Nullable Union
    
    int null Type
  - Example
    
    int|string|float
- Weak Map
  - WeakMap Class
    
    Weak Reference Map
- Stringable
  - Stringable Interface
    
    toString Implementation
- String Functions
  - str_contains
    
    Check String Contains Substring
  - str_starts_with
    
    Check String Starts With
  - str_ends_with
    
    Check String Ends With
- Debug Functions
  - get_debug_type
    
    Get Better Type Name
  - get_resource_id
    
    Get Resource ID
- Throw Expression
  - Throw in Expression
    
    Throw Exception in One Line
PHP 8.1 Features
- Enums
  - Enum Keyword
    
    PHP 8.1 Enumerations
  - Pure Enum
    
    enum Suit case Hearts
  - Backed Enum
    
    enum Status string case Pending
  - Enum Methods
    
    Enums Can Have Methods
  - Enum Constants
    
    Enums Can Have Constants
  - Enum in Switch
    
    Use Enum in Switch Cases
  - From Method
    
    BackedEnum from Value
  - TryFrom Method
    
    Returns Null if Invalid
- Readonly Properties
  - Readonly Keyword
    
    Property Write Once
- Readonly Class
  - Readonly Class
    
    All Properties Readonly
- First Class Callable
  - Callable Syntax
    
    fnName Three Dots
- Array Unpacking
  - String Keys
    
    String Keys Support
- Never Type
  - Never Return Type
    
    Function Never Returns
- Fibers
  - Fiber Introduction
    
    Lightweight Concurrency
  - Fiber Start
    
    new Fiber start
  - Fiber Resume
    
    resume Method
  - Fiber Return
    
    getReturn Method
- Array Functions
  - array_is_list
    
    Check if List Array
- Final Constants
  - final Keyword
    
    Final Class Constants
- Intersection Types
  - Intersection Syntax
    
    Countable Traversable
PHP 8.2 Features
- Readonly Classes
  - Readonly Class
    
    All Properties Readonly
- DNF Types
  - Complex Types
    
    Union Intersection Combination
- Trait Constants
  - Constants in Traits
    
    Traits Can Have Constants
- Random Extension
  - Randomizer Class
    
    New Random Generator
PHP 8.3 Features
- Class Constant Typing
  - Constant Types
    
    Type Declaration for Constants
- Dynamic Constant Fetch
  - Class Constant Fetch
    
    Dynamic Class Constant Access
- json_validate
  - Validate JSON
    
    Check JSON Without Parsing
PHP 8.4 Features
- Property Hooks
  - Get Set Hooks
    
    get set Property Hooks
- Asymmetric Visibility
  - Public Get Private Set
    
    Different Read Write Visibility
- Array Functions
  - array_find
    
    Find Element by Callback
  - array_find_key
    
    Find Key by Callback
  - array_any
    
    Check Any Element Matches
  - array_all
    
    Check All Elements Match
PHP Composer
- Introduction
  - What is Composer
    
    Dependency Manager for PHP
  - Package Manager
    
    Manage PHP Libraries
  - Inspiration
    
    Inspired by npm and bundler
- Installation
  - Download Composer
    
    Get composer.phar File
  - Global Install
    
    Mov to usr local bin
  - Windows Installer
    
    Download Composer Setup Exe
  - Verify Install
    
    composer Command Check
- composer.json
  - Create File
    
    composer init Command
  - Name Field
    
    vendor project Format
  - Description Field
    
    Package Description Text
  - Type Field
    
    library project metapackage
  - License Field
    
    Open Source License Name
  - Authors Field
    
    Developer Information Array
  - Require Field
    
    Production Dependencies List
  - Require Dev Field
    
    Development Dependencies List
  - Autoload Field
    
    PSR-4 Namespace Mapping
  - Autoload Dev Field
    
    Development Autoload Rules
  - Scripts Field
    
    Composer Hooks Definition
  - Minimum Stability
    
    Allow dev beta rc stable
  - Prefer Stable
    
    Prefer Stable Packages Flag
- Version Constraints
  - Exact Version
    
    1.2.3 Exact Match
  - Caret Range
    
    ^1.0 Allows 1.x
  - Tilde Range
    
    ~1.2 Allows 1.2.x
  - Hyphen Range
    
    1.0 - 2.0 Range
  - Wildcard Version
    
    1.0.* Wildcard
  - Greater Than
    
    >=1.0 Minimum Version
  - Less Than
    
    <2.0 Maximum Version
  - Dev Versions
    
    dev-master Development
  - Stability Flags
    
    @dev @beta @rc
- Commands
  - composer install
    
    Install from Lock File
  - composer update
    
    Update to Latest Versions
  - composer require
    
    Add New Package
  - composer require dev
    
    Add Dev Package
  - composer remove
    
    Remove Package
  - composer show
    
    Show Package Information
  - composer outdated
    
    Show Outdated Packages
  - composer why
    
    Show Why Package Installed
  - composer validate
    
    Validate composer.json File
  - composer dump-autoload
    
    Regenerate Autoloader
  - composer clear-cache
    
    Clear Composer Cache
  - composer self-update
    
    Update Composer Version
- composer.lock
  - Lock File Purpose
    
    Pin Exact Package Versions
  - Commit Lock File
    
    Commit to Version Control
  - Version Control
    
    Ensure Same Versions Everywhere
- vendor Directory
  - Third Party Code
    
    All Dependencies Here
  - autoload.php
    
    Include for Autoloading
  - Do Not Commit
    
    Add to gitignore
- Autoloading
  - PSR-4 Standard
    
    Namespace to Directory Mapping
  - PSR-4 Config
    
    App Backslash App Directory
  - PSR-0 Standard
    
    Deprecated Autoload Standard
  - Classmap Autoload
    
    Legacy Libraries Support
  - Files Autoload
    
    Global Helper Functions
  - Dump Autoload
    
    Regenerate After Changes
- Packagist
  - Official Repository
    
    Packagist.org Website
  - Search Packages
    
    Find PHP Libraries
  - Submit Package
    
    Publish Your Library
- Custom Repository
  - VCS Repository
    
    Git GitHub Bitbucket
  - Path Repository
    
    Local Development Package
  - Pear Repository
    
    Legacy PEAR Packages
- Scripts
  - Pre Install Cmd
    
    Before Install Hook
  - Post Install Cmd
    
    After Install Hook
  - Pre Update Cmd
    
    Before Update Hook
  - Post Update Cmd
    
    After Update Hook
  - Pre Autoload Dump
    
    Before Autoload Generation
  - Post Autoload Dump
    
    After Autoload Generation
  - Pre Package Install
    
    Before Package Install
  - Post Package Install
    
    After Package Install
  - Execute PHP Script
    
    @php runner php
  - Execute Composer
    
    @composer command
- Creating Package
  - composer.json Requirements
    
    Name and Description Required
  - Add Version
    
    Version Field or Git Tag
  - Packagist Submission
    
    Submit to Packagist
  - Autoload Setup
    
    PSR-4 Configuration
- Optimization
  - Classmap Optimization
    
    #NAME?
  - APCu Autoloader
    
    apcu-autoloader Flag
  - Production Build
    
    Use Optimized Autoloader
PHP Unit Testing
- PHPUnit
  - Introduction
    
    Unit Testing Framework
  - Installation
    
    Composer require phpunit
  - Version
    
    PHPUnit 10 for PHP 8.1
  - Test Class
    
    Extend TestCase Class
  - Test Method
    
    public function testMethod
  - Test Naming
    
    test Prefix Convention
  - Test Annotation
    
    @test Annotation Alternative
- Assertions
  - assertEquals
    
    Expected vs Actual Value
  - assertSame
    
    Strict Type Comparison
  - assertTrue
    
    Check Condition True
  - assertFalse
    
    Check Condition False
  - assertNull
    
    Check Value is Null
  - assertNotNull
    
    Check Value Not Null
  - assertEmpty
    
    Check Value Empty
  - assertNotEmpty
    
    Check Value Not Empty
  - assertCount
    
    Check Array Length
  - assertContains
    
    Check Value in Array
  - assertNotContains
    
    Check Value Not in Array
  - assertStringContainsString
    
    Check Substring in String
  - assertStringNotContainsString
    
    Check Substring Absent
  - assertMatchesRegularExpression
    
    Check Regex Pattern
  - assertFileExists
    
    Check File Exists
  - assertFileEquals
    
    Check Files Identical
  - assertJson
    
    Check Valid JSON String
  - assertJsonStringEqualsJsonString
    
    Compare JSON Content
- Annotations
  - @dataProvider
    
    Test with Data Sets
  - @depends
    
    Dependent Test Method
  - @group
    
    Group Tests Together
  - @covers
    
    Specify Tested Class
  - @coversMethod
    
    Specify Tested Method
  - @large
    
    Slow Running Test Flag
- Fixtures
  - setUp
    
    Run Before Each Test
  - tearDown
    
    Run After Each Test
  - setUpBeforeClass
    
    Run Once Before Class
  - tearDownAfterClass
    
    Run Once After Class
- Exceptions
  - expectException
    
    Expect Exception Type
  - expectExceptionMessage
    
    Expect Exception Message
  - expectExceptionCode
    
    Expect Exception Code
- Test Doubles
  - createMock
    
    Create Mock Object
  - getMockBuilder
    
    Advanced Mock Creation
- Mock Methods
  - expects
    
    Set Method Expectation
  - willReturn
    
    Specify Return Value
  - willReturnCallback
    
    Return from Callback
  - willThrowException
    
    Throw Exception
  - with
    
    Parameter Constraints
- Mock Counts
  - once
    
    Expect One Call
  - never
    
    Expect No Calls
  - exactly
    
    Exact Number of Calls
  - any
    
    Any Number of Calls
- phpunit.xml
  - Configuration File
    
    Project Configuration
  - directory Suite
    
    Test Directory Path
  - file Suite
    
    Specific Test File
  - exclude
    
    Exclude Directory
- Command Line
  - #NAME?
    
    Run Specific Test
    
    Run Grouped Tests
    
    Exclude Test Groups
    
    Readable Output Format
    
    Enable Color Output
    
    Stop on First Failure
- Code Coverage
  - Xdebug Required
    
    Enable Code Coverage
  - #NAME?
    
    HTML Report Generation
    
    Clover XML Report
    
    Console Coverage Report
- Best Practices
  - One Assertion Per Test
    
    Keep Tests Focused
  - Test Names Clear
    
    Describe Test Purpose
  - Independent Tests
    
    Tests Should Not Depend
PHP Laravel
- Laravel Introduction
  - What is Laravel
    
    Popular PHP Framework
- Laravel Features
  - Eloquent ORM
    
    Active Record Implementation
  - Blade Templating
    
    Template Engine
  - Artisan CLI
    
    Command Line Tool
  - Routing System
    
    Clean Route Definitions
  - Migrations
    
    Database Version Control
- Installation
  - Composer Create
    
    composer create-project laravel
  - Laravel Installer
    
    laravel new project
  - Requirements
    
    PHP 8.1 or Higher
- Artisan Commands
  - php artisan make:model
    
    Create Model Class
  - php artisan make:controller
    
    Create Controller
  - php artisan make:migration
    
    Create Migration
  - php artisan migrate
    
    Run Migrations
  - php artisan tinker
    
    Interactive Shell
  - php artisan route:list
    
    List All Routes
  - php artisan cache:clear
    
    Clear Application Cache
- Routing
  - web.php File
    
    Web Routes Definition
  - api.php File
    
    API Routes Definition
  - Route Methods
    
    get post put delete
  - Route Parameters
    
    Route Parameter Binding
  - Named Routes
    
    Route Name Method
  - Route Groups
    
    Group Middleware Prefix
- Controllers
  - Make Controller
    
    php artisan make:controller
  - Resource Controller
    
    CRUD Methods Automatically
  - Invokable Controller
    
    Single Action Controller
- Views
  - Blade Files
    
    blade.php Extension
  - Blade Echo
    
    Double Brace Syntax
  - Blade Directives
    
    @if @foreach @section
  - Blade Components
    
    Reusable UI Components
- Eloquent
  - Model Creation
    
    php artisan make:model
  - Model Properties
    
    fillable guarded table
  - CRUD Operations
    
    create update delete find
  - Relationships
    
    hasMany belongsTo belongsToMany
- Migrations
  - Schema Builder
    
    Create and Modify Tables
  - Up Method
    
    Apply Migration Changes
  - Down Method
    
    Revert Migration Changes
- Validation
  - Request Validation
    
    validate Method
  - Form Request
    
    Custom Request Classes
  - Rules List
    
    required email unique
- Authentication
  - php artisan make:auth
    
    Generate Auth Scaffolding
  - Auth Facade
    
    Authentication Methods
  - Authentication Guards
    
    web api Guards
PHP Symfony
- Symfony Introduction
  - What is Symfony
    
    Modular PHP Framework
- Symfony Features
  - Reusable Components
    
    Standalone Libraries
- Symfony Installation
  - Composer Create
    
    composer create-project symfony
- Symfony Console
  - bin/console
    
    Command Line Tool
- Symfony Components
  - HttpFoundation
    
    Request Response Handling
  - Routing
    
    Advanced Routing System
  - Validator
    
    Validation Component
  - DependencyInjection
    
    Service Container
- Doctrine ORM
  - Doctrine Introduction
    
    Object Relational Mapping
  - Entities
    
    Database Mapped Classes
  - Repositories
    
    Database Query Methods
- Twig Templating
  - Twig Introduction
    
    Template Engine
- Twig Syntax
  - Double Brace Echo
    
    Curly Brace Syntax
- Routing Attributes
  - Routing Configuration
    
    PHP 8 Attributes
PHP CodeIgniter
- CodeIgniter Introduction
  - What is CodeIgniter
    
    Lightweight PHP Framework
- CodeIgniter Features
  - Small Footprint
    
    Minimal Configuration
- CodeIgniter Installation
  - Download and Extract
    
    Simple Setup
- MVC Pattern
  - Models
    
    Database Logic Layer
  - Views
    
    Presentation Layer
  - Controllers
    
    Request Handler Layer
- Configuration
  - Config Files
    
    Database Autoload Config
- Database Query Builder
  - Query Builder Class
    
    Fluent Interface for Queries
PHP WordPress
- WordPress Introduction
  - What is WordPress
    
    PHP CMS Platform
- WordPress Hooks
  - Actions
    
    do_action add_action
  - Filters
    
    apply_filters add_filter
- Plugin Development
  - Plugin Header
    
    Plugin Metadata Comment
  - Activation Hook
    
    register_activation_hook
  - Deactivation Hook
    
    register_deactivation_hook
- Theme Development
  - functions.php
    
    Theme Functions File
  - Template Files
    
    index php single php page php
  - Template Hierarchy
    
    WordPress File Naming
- Custom Post Types
  - register_post_type
    
    Create Custom Content Types
- WP_Query
  - Custom Queries
    
    Advanced Database Queries
PHP Caching
- OPcache
  - Introduction
    
    Opcode Caching
  - Enable Setting
    
    opcache.enable Directive
  - Memory Setting
    
    opcache.memory_consumption
  - Validation Setting
    
    opcache.validate_timestamps
  - Reset Function
    
    opcache_reset Function
- APCu
  - Introduction
    
    User Data Caching
  - Installation
    
    pecl install apcu
  - Store Data
    
    apcu_store Function
  - Fetch Data
    
    apcu_fetch Function
  - Delete Data
    
    apcu_delete Function
  - Check Exists
    
    apcu_exists Function
  - Clear Cache
    
    apcu_clear_cache Function
- Memcached
  - Introduction
    
    Distributed Memory Caching
  - Installation
    
    apt-get install memcached
  - PHP Extension
    
    pecl install memcached
  - Connect Server
    
    new Memcached addServer
  - Set Data
    
    memcached set Method
  - Get Data
    
    memcached get Method
  - Delete Data
    
    memcached delete Method
  - Increment Value
    
    memcached increment Method
  - Decrement Value
    
    memcached decrement Method
- Redis
  - Introduction
    
    Advanced Key Value Store
  - Installation
    
    apt-get install redis-server
  - PHP Extension
    
    pecl install redis
  - Connect Server
    
    new Redis connect
  - Set Value
    
    redis set Method
  - Get Value
    
    redis get Method
  - Set Expiry
    
    redis expire Method
  - Delete Key
    
    redis del Method
  - Increment Value
    
    redis incr Method
  - Hash Operations
    
    redis hSet hGet hDel
  - Pub Sub
    
    redis publish subscribe
- Page Caching
  - Output Buffering
    
    ob_start Function
  - Check Cache
    
    Verify Cache File Exists
  - Save Cache
    
    file_put_contents Cache
  - Serve Cache
    
    Read and Output Cache File
  - Cache Invalidation
    
    Delete on Content Update
- Query Caching
  - Cache Results
    
    Cache Database Query Results
- Cache Strategies
  - Cache Hit Ratio
    
    Monitor Effectiveness
  - Cache Stampede
    
    Prevent Multiple Writes
PHP Command Line
- CLI Basics
  - What is PHP CLI
    
    Command Line Interface
- CLI vs Web
  - No HTTP Headers
    
    Different php.ini File
- Running Scripts
  - Execute PHP File
    
    php script.php
- Interactive Shell
  - php -a
    
    Interactive PHP Shell
- Run Code Direct
  - php -r
    
    Execute One Liner
- Built-in Server
  - php -S
    
    Start Development Server
- Built-in Server Router
  - php -S router.php
    
    Router File for Server
- Command Arguments
  - $argv Array
    
    Arguments Passed to Script
- Argument Count
  - $argc Variable
    
    Number of Arguments
- Script Name
  - $argv 0
    
    Script File Name
- First Argument
  - $argv 1
    
    First User Argument
- STDIN Stream
  - php stdin
    
    Standard Input Stream
- STDOUT Stream
  - php stdout
    
    Standard Output Stream
- STDERR Stream
  - php stderr
    
    Standard Error Stream
- Read STDIN
  - fopen stdin
    
    Open Standard Input
- Read Line
  - fgets STDIN
    
    Read Single Line
- Write STDOUT
  - fwrite STDOUT
    
    Write to Output
- Write Error
  - fwrite STDERR
    
    Write to Error
- getopt Function
  - Parse Options
    
    Parse Command Line Options
- getopt Example
  - getopt a b
    
    Short Option Parsing
- getopt Long
  - getopt option
    
    Long Option Parsing
- Exit Codes
  - exit 0
    
    Success Exit Code
  - exit 1
    
    Failure Exit Code
- Environment Variables
  - getenv Function
    
    Get Environment Variable
  - putenv Function
    
    Set Environment Variable
- CLI Detection
  - PHP SAPI
    
    Check if CLI Mode
- Terminal Colors
  - ANSI Codes
    
    Color Output Codes
- Text Color
  - 033 32m
    
    Green Text Code
- Background Color
  - 033 41m
    
    Red Background Code
- Reset Color
  - 033 0m
    
    Reset to Default
- Progress Bar
  - CLI Progress
    
    Text Progress Indicator
- Table Output
  - Format Table
    
    Display Data as Table
- Spinner Animation
  - CLI Spinner
    
    Loading Animation
- Symfony Console
  - Console Component
    
    CLI Framework
- Symfony Command
  - Extend Command
    
    Create CLI Command
- Symfony Input
  - Input Interface
    
    Arguments and Options
- Symfony Output
  - Output Interface
    
    Styled Output
PHP Cron Jobs
- Cron Introduction
  - Cron Jobs
    
    Scheduled Tasks on Linux
PHP Design Patterns
- Singleton Pattern
  - Definition
    
    Single Instance Class
  - Private Constructor
    
    Prevent Direct Instantiation
  - Private Clone
    
    Prevent Cloning
  - getInstance Method
    
    Return Single Instance
  - Database Example
    
    Singleton DB Connection
- Factory Pattern
  - Definition
    
    Create Objects Without Specification
  - Simple Factory
    
    Static Method Creation
  - Factory Method
    
    Subclass Decides Type
  - Abstract Factory
    
    Family of Related Objects
  - Payment Example
    
    PayPal Stripe Factory
- Strategy Pattern
  - Definition
    
    Family of Algorithms
  - Strategy Interface
    
    Common Algorithm Interface
  - Context Class
    
    Maintains Strategy Reference
  - Payment Strategy
    
    Multiple Payment Methods
  - Dynamic Change
    
    Switch at Runtime
- Observer Pattern
  - Definition
    
    Subject Observer Relationship
  - SplSubject Interface
    
    Subject Interface
  - SplObserver Interface
    
    Observer Interface
  - attach Method
    
    Add Observer
  - detach Method
    
    Remove Observer
  - notify Method
    
    Notify All Observers
  - Event System
    
    Event Listeners Example
- Decorator Pattern
  - Definition
    
    Add Behavior Without Modifying
  - Component Interface
    
    Original Interface
  - Concrete Component
    
    Base Implementation
  - Decorator Class
    
    Wraps Component
  - Caching Example
    
    Add Cache to Repository
  - Logging Example
    
    Add Logging to Service
- Adapter Pattern
  - Definition
    
    Convert Interface to Another
  - Target Interface
    
    Expected Interface
  - Adaptee Class
    
    Existing Class
  - Adapter Class
    
    Bridges Target Adaptee
  - Payment Example
    
    Stripe to PayPal Adapter
- Repository Pattern
  - Definition
    
    Separate Data Logic
  - Repository Interface
    
    Data Access Contract
  - Concrete Repository
    
    Database Implementation
  - User Repository
    
    CRUD for User Entity
  - Repository Cache
    
    Decorator for Caching
- Dependency Injection
  - Definition
    
    Pass Dependencies via Constructor
  - Constructor Injection
    
    Most Common Method
  - Setter Injection
    
    Optional Dependencies
  - Interface Injection
    
    Contract Based
  - Service Container
    
    Autowiring Dependencies
  - Benefits
    
    Testability Flexibility
- MVC Pattern
  - Definition
    
    Model View Controller
  - Model
    
    Business Logic Layer
  - View
    
    Presentation Template Layer
  - Controller
    
    Request Handler Layer
  - Routing
    
    Map URLs to Controllers
  - Dispatcher
    
    Load Controller Execute
- Front Controller Pattern
  - Definition
    
    Single Entry Point
  - index.php
    
    Front Controller File
  - Routing Logic
    
    Determine Controller from URL
  - Bootstrap
    
    Initialize Application
PHP Projects
- Login System
  - User Registration
    
    Create New User Account
  - Password Hashing
    
    Store Secure Passwords
  - Login Validation
    
    Verify User Credentials
  - Session Creation
    
    Start User Session
  - Remember Me Feature
    
    Long Term Cookie Login
  - Password Reset
    
    Send Reset Email Link
  - Email Verification
    
    Verify User Email Address
  - Two Factor Authentication
    
    Extra Security Layer
  - Account Lockout
    
    Bad Attempts Limit
  - Logout Function
    
    Destroy User Session
- CRUD Application
  - Create Record
    
    Insert New Database Entry
  - Read Records
    
    Display Database Entries
  - Update Record
    
    Modify Existing Entry
  - Delete Record
    
    Remove Database Entry
  - Search Functionality
    
    Filter Records by Keyword
  - Pagination Feature
    
    Split Records Across Pages
  - Sort Records
    
    Order by Column
  - Export to CSV
    
    Download Records as CSV
  - Import from CSV
    
    Bulk Upload Records
  - AJAX CRUD
    
    Submit Without Page Reload
- REST API
  - User Endpoint
    
    List Create Users
    
    Register Login Profile
  - User Show Endpoint
    
    Get Single User
  - User Update Endpoint
    
    Modify User Data
  - User Delete Endpoint
    
    Remove User Record
  - API Authentication
    
    API Key Validation
  - JWT Implementation
    
    Generate and Verify Tokens
  - Rate Limiting
    
    Limit API Requests
  - API Versioning
    
    Support Multiple Versions
  - Error Handling
    
    Return Proper Status Codes
  - Response Formatting
    
    Consistent JSON Structure
  - JWT Authentication
    
    Generate and Verify Tokens
  - Product Endpoint
    
    CRUD for Products
  - Order Endpoint
    
    Create View Orders
  - API Documentation
    
    Swagger Integration
- File Manager
  - Upload Files
    
    Handle File Uploads
  - List Files
    
    Display Directory Contents
  - Preview Images
    
    Show Image Thumbnails
  - Download Files
    
    Force File Download
  - Delete Files
    
    Remove from Server
  - Rename Files
    
    Change File Names
  - Create Folders
    
    Make New Directories
  - Move Files
    
    Change File Location
  - Search Files
    
    Find by File Name
  - File Information
    
    Show Size Type Date
- Shopping Cart
  - Add to Cart
    
    Store Product in Cart
  - View Cart
    
    Display Cart Items
  - Update Quantity
    
    Change Item Count
  - Remove Item
    
    Delete from Cart
  - Coupon System
    
    Apply Discount Codes
  - Calculate Total
    
    Sum All Items
  - Checkout Process
    
    Collect User Details
  - Order Confirmation
    
    Save Order to Database
  - Email Receipt
    
    Send Order Summary
  - Payment Integration
    
    Stripe PayPal Gateway
- Blog System
  - Create Post
    
    Write New Blog Entry
    
    Add New Blog Post
  - Edit Post
    
    Modify Existing Content
    
    Modify Existing Post
  - Delete Post
    
    Remove Blog Entry
    
    Remove Post Permanently
  - Display Posts
    
    Show All Blog Entries
    
    Show All Posts List
  - Single Post View
    
    Show Full Article
    
    Show Full Post Content
  - Categories
    
    Group Related Posts
  - Tags
    
    Add Post Labels
  - Comments System
    
    User Feedback on Posts
  - Post Search
    
    Find by Title Content
  - Post Pagination
    
    Split Posts Across Pages
  - SEO Friendly URLs
    
    Clean URL Structure
  - Database Schema
    
    Posts Categories Comments Tables
  - Category Management
    
    Group Posts by Category
  - Tag System
    
    Label Posts with Tags
  - Comment System
    
    User Comments on Posts
  - Search Functionality
    
    Find Posts by Keyword
  - Pagination Feature
    
    Split Posts Across Pages
- Task Manager
  - Create Task
    
    Add New Task Item
  - Edit Task
    
    Modify Task Details
  - Delete Task
    
    Remove Task Permanently
  - Mark Complete
    
    Set Task Status Done
  - Due Dates
    
    Set Task Deadlines
  - Priority Levels
    
    High Medium Low
  - Filter Tasks
    
    Show by Status
  - Sort Tasks
    
    Order by Date Priority
  - Search Tasks
    
    Find by Title Description
  - Task Dashboard
    
    Summary Statistics
- Contact Form
  - Build Form
    
    Create HTML Contact Form
  - Validate Input
    
    Check Required Fields
  - Sanitize Data
    
    Remove Dangerous Characters
  - CSRF Protection
    
    Add Security Token
  - CAPTCHA Integration
    
    Prevent Bot Spam
  - Send Email
    
    Use PHPMailer
  - Auto Reply
    
    Send Confirmation Email
  - Save to Database
    
    Store Contact Messages
  - Admin Notification
    
    Alert New Message
  - Spam Filtering
    
    Block Suspicious Content
- Dashboard
  - Statistics Cards
    
    Show Key Metrics
  - Charts Integration
    
    Visual Data Display
  - Recent Activity
    
    Show Latest Actions
  - User Management
    
    List All Users
  - Role Management
    
    Assign User Permissions
  - Settings Page
    
    Update Application Config
  - Report Generation
    
    Create PDF Reports
  - Export Data
    
    Download as Excel CSV
  - Activity Logs
    
    Track User Actions
  - Notification System
    
    Alert Important Events
- WebSocket Chat
  - Server Setup
    
    Ratchet WebSocket Server
  - Client Connection
    
    JavaScript WebSocket API
  - Send Message
    
    Broadcast to All Users
  - Private Messages
    
    Direct User Chat
  - User Typing
    
    Show Typing Indicator
  - Online Status
    
    Show Active Users
  - Message History
    
    Store in Database
  - File Sharing
    
    Send Images Files
  - Emoji Support
    
    Add Reaction Icons
  - Notification Sounds
    
    Alert New Messages
- PDF Generator
  - HTML to PDF
    
    Use dompdf Library
  - Invoice Creation
    
    Generate Order Invoice
  - Report PDF
    
    Create Data Reports
  - Certificate Maker
    
    Generate Achievement PDF
  - Table Layout
    
    Display Data Tables
  - Header Footer
    
    Add Page Numbers
  - Watermark Add
    
    Protect PDF Document
  - Password Protection
    
    Secure PDF Files
  - Email PDF
    
    Send as Email Attachment
  - Batch Generation
    
    Create Multiple PDFs
- Excel Export
  - Export to XLSX
    
    Use PhpSpreadsheet
  - Multiple Sheets
    
    Create Workbook Tabs
  - Format Cells
    
    Set Colors Borders Fonts
  - Add Formulas
    
    Calculate in Excel
  - Export from Database
    
    Fetch and Write Data
  - Export with Headers
    
    Column Names First Row
  - CSV Export
    
    Simple Comma Separated
- Excel Import
  - Read Excel File
    
    Load and Parse Data
  - Validate Data
    
    Check Required Fields
  - Import to Database
    
    Bulk Insert Records
  - Error Reporting
    
    Show Failed Rows
- Image Gallery
  - Upload Images
    
    Store Image Files
  - Create Thumbnails
    
    Resize with GD
  - Display Gallery
    
    Show Image Grid
  - Lightbox View
    
    Popup Image Viewer
  - Image Categories
    
    Group by Album
  - Add Watermark
    
    Protect Image Copyright
  - Image Delete
    
    Remove from Server
  - Bulk Upload
    
    Multiple Files at Once
  - Search Images
    
    Find by Name Tag
  - Image Comments
    
    User Feedback on Images
- Newsletter System
  - Subscribe Form
    
    Collect Email Addresses
  - Double Opt-In
    
    Send Confirmation Email
  - Unsubscribe Link
    
    Remove from List
  - Manage Subscribers
    
    Admin Panel Control
  - Create Campaign
    
    Write Newsletter Content
  - Send Newsletter
    
    Bulk Email Sending
  - Queue System
    
    Process Large Batches
  - Open Tracking
    
    Know Who Read Email
  - Click Tracking
    
    Monitor Link Clicks
  - Analytics Dashboard
    
    Show Campaign Stats
- URL Shortener
  - Create Short URL
    
    Generate Unique Code
  - Redirect Logic
    
    Forward to Original URL
  - Custom Alias
    
    User Defined Short Codes
  - QR Code Generator
    
    Create QR for Short URL
  - Click Counter
    
    Track Visit Statistics
  - Analytics Page
    
    Show Referrer Device
  - API Support
    
    Programmatic URL Creation
  - Link Expiry
    
    Set Expiration Date
  - Password Protection
    
    Secure Shared Links
  - Bulk Shorten
    
    Multiple URLs at Once
- Poll System
  - Create Poll
    
    Question and Options
  - Display Poll
    
    Show Voting Interface
  - Submit Vote
    
    Save User Selection
  - Prevent Double Voting
    
    Restrict Duplicate Votes
  - Show Results
    
    Display Vote Counts
  - Results Chart
    
    Visual Data Representation
  - Multiple Polls
    
    Manage Different Topics
  - Poll Status
    
    Open Close Voting
  - Comments Section
    
    Discuss Poll Topic
  - Export Results
    
    Download Vote Data
- Quiz System
  - Create Quiz
    
    Questions and Answers
  - Display Question
    
    Show One by One
  - Submit Answer
    
    Save User Response
  - Calculate Score
    
    Count Correct Answers
  - Show Result
    
    Display Final Score
  - Leaderboard
    
    Top Scorers List
  - Time Limit
    
    Restrict Quiz Duration
  - Random Questions
    
    Shuffle Question Order
  - Multiple Attempts
    
    Allow Retake Quiz
  - Certificate Generation
    
    Award on Passing
- Expense Tracker
  - Add Expense
    
    Record New Transaction
  - Edit Expense
    
    Modify Existing Entry
  - Delete Expense
    
    Remove Transaction
  - Categories
    
    Group Expenses by Type
  - Dashboard
    
    Show Total Spending
  - Monthly Report
    
    View by Month
  - Yearly Report
    
    Annual Summary
  - Budget Setting
    
    Define Spending Limits
  - Chart Display
    
    Visual Expense Breakdown
  - Export Report
    
    Download PDF Excel
- Ecommerce Cart
  - Product Management
    
    Add Edit Delete Products
  - Add to Cart Function
    
    Store Product in Session
  - View Cart Page
    
    Display Cart Items
  - Update Quantity
    
    Change Item Count
  - Remove Item
    
    Delete from Cart
  - Coupon System
    
    Apply Discount Codes
  - Calculate Total
    
    Sum All Item Prices
  - Checkout Process
    
    Collect Customer Details
  - Order Confirmation
    
    Save Order to Database
  - Email Receipt
    
    Send Order Summary Email
  - Payment Integration
    
    Stripe PayPal Gateway
- Real-time Chat
  - Ratchet Server Setup
    
    WebSocket Server
  - Client Connection
    
    JavaScript WebSocket
  - Send Message
    
    Broadcast to All Users
  - Private Message
    
    Direct User Chat
  - User Typing
    
    Show Typing Indicator
  - Online Status
    
    Show Active Users
  - Message History
    
    Store in Database
  - File Sharing
    
    Send Images Files
  - Emoji Support
    
    Add Reaction Icons
  - Notification Sound
    
    Alert New Messages
- CRUD Generator
  - Database Connection
    
    PDO Configuration
  - Table Listing
    
    Show All Database Tables
  - Generate Create Form
    
    HTML Form Generator
  - Generate Read List
    
    Data Table Generator
  - Generate Update Form
    
    Edit Form Generator
  - Generate Delete Feature
    
    Safe Delete Code
  - Code Output Display
    
    Show Generated Code
  - Download Feature
    
    Save Generated Files
PHP Advanced Topics
- Web Scraping
  - cURL Requests
    
    Fetch External Pages
  - DOM Parsing
    
    Extract HTML Elements
  - XPath Queries
    
    Navigate XML HTML
  - Regular Expressions
    
    Extract Patterns
  - Crawl Multiple Pages
    
    Follow Pagination
  - Delay Requests
    
    Avoid Rate Limiting
  - User Agent Spoofing
    
    Identify as Browser
  - Handle JavaScript
    
    Use Headless Browser
  - Parse JSON APIs
    
    Extract JSON Data
  - Save Scraped Data
    
    Store in Database
- Queue Systems
  - Beanstalkd Setup
    
    Install Queue Server
  - Put Job in Queue
    
    Add Task to Queue
  - Process Queue
    
    Worker Script Execution
  - Retry Failed Jobs
    
    Handle Processing Errors
  - Delayed Jobs
    
    Schedule Future Processing
  - Priority Levels
    
    Process Important First
  - Queue Monitoring
    
    Track Job Status
  - RabbitMQ PHP
    
    AMQP Protocol Implementation
  - Redis Queue
    
    Use Redis for Queues
  - Database Queue
    
    Simple Table Based Queue
- Event Broadcasting
  - Event Class
    
    Define Event Object
  - Listener Class
    
    Handle Event Occurrence
  - Event Dispatcher
    
    Trigger Events
  - Async Events
    
    Queue for Performance
  - WebSocket Push
    
    Real Time Updates
  - Laravel Events
    
    Easy Event System
  - Logging Events
    
    Track System Activity
  - User Notifications
    
    Send on Events
  - Email on Event
    
    Trigger Email Alerts
- Middleware
  - What is Middleware
    
    Filter HTTP Requests
  - Before Middleware
    
    Process Before Controller
  - After Middleware
    
    Process After Controller
  - Authentication Middleware
    
    Check User Login
  - Admin Middleware
    
    Verify Admin Role
  - Rate Limit Middleware
    
    Throttle Requests
  - CORS Middleware
    
    Add Headers to Response
  - Logging Middleware
    
    Record All Requests
  - Custom Middleware
    
    Build Your Own
- Service Container
  - What is Container
    
    Dependency Management
  - Bind Interface
    
    Register Implementation
  - Resolve Class
    
    Auto Create Instance
  - Singleton Binding
    
    Single Instance Per Request
  - Contextual Binding
    
    Different Implementations
  - Service Providers
    
    Group Related Bindings
  - Deferred Provider
    
    Lazy Loading Service
  - Tagged Services
    
    Group Multiple Services
  - PSR-11 Container
    
    Standard Container Interface
  - Container Aware
    
    Services Knowing Container
- Database Migrations
  - Create Migration
    
    Define Schema Changes
  - Up Method
    
    Apply Database Changes
  - Down Method
    
    Revert Database Changes
  - Rollback Command
    
    Undo Last Migration
  - Migrate Refresh
    
    Rollback and Remigrate
  - Seed Database
    
    Insert Default Data
  - Faker Library
    
    Generate Fake Data
  - Data Types
    
    String Integer Timestamp
  - Table Indexes
    
    Improve Query Speed
  - Foreign Keys
    
    Define Relationships
- Database Seeding
  - Create Seeders
    
    Generate Test Data
  - Factory Pattern
    
    Bulk Data Generation
  - Relationships Seeding
    
    Create Related Data
  - Environment Specific
    
    Dev vs Production
  - Truncate First
    
    Clear Existing Data
  - Seed from CSV
    
    Import External Data
  - Seed with Images
    
    Generate Test Files
  - Database Refresh
    
    Run All Seeders
- API Documentation
  - OpenAPI Specification
    
    Standard API Docs
  - Swagger UI
    
    Interactive Documentation
  - Generate from Code
    
    Annotations to Docs
  - Postman Collection
    
    Export API Definition
  - Redoc Tool
    
    Clean Documentation Viewer
  - Versioning in Docs
    
    Multiple API Versions
  - Authentication Docs
    
    Show Auth Methods
  - Request Examples
    
    Show Sample Requests
  - Response Examples
    
    Show Expected Output
  - Error Documentation
    
    List Error Codes
- Code Profiling
  - Xdebug Profiler
    
    Analyze Performance
  - Blackfire io
    
    Performance Monitoring
  - Tideways Service
    
    Production Profiling
  - Memory Profiling
    
    Check Memory Usage
  - Time Profiling
    
    Find Slow Functions
  - Query Profiling
    
    Analyze Database Queries
  - Call Graph
    
    Visual Function Calls
  - Profile in Production
    
    Use Sampling
  - Compare Profiles
    
    Before After Changes
  - Continuous Profiling
    
    Always on Profiling
- Code Linting
  - PHP Linter
    
    Check Syntax Errors
  - PSR Standards
    
    Follow Coding Standards
  - Code Sniffer
    
    Detect Style Violations
  - Static Analysis
    
    Find Bugs Without Running
  - Psalm Tool
    
    Advanced Static Analysis
  - PhpStan Tool
    
    Catch Type Errors
  - IDE Integration
    
    Linting in Editor
  - Git Hooks
    
    Lint Before Commit
  - CI Integration
    
    Automated Code Checks
  - Fix Automatically
    
    Use PHPCBF
- GraphQL API
  - GraphQL Introduction
    
    Query Language for APIs
  - GraphQL Schema
    
    Define Types Queries Mutations
  - GraphQL Query
    
    Fetch Specific Data Fields
  - GraphQL Mutation
    
    Modify Server Data
  - GraphQL PHP Library
    
    webonyx graphql-php
  - Resolvers Functions
    
    Fetch Data for Fields
  - GraphQL vs REST
    
    Single Endpoint Advantage
  - GraphQL Client
    
    Apollo or URQL
  - GraphQL Playground
    
    Interactive Documentation Tool
  - Nested Queries
    
    Fetch Related Data
- Microservices Architecture
  - What is Microservices
    
    Small Independent Services
  - API Gateway
    
    Single Entry Point
  - Service Discovery
    
    Find Service Locations
  - Inter Service Communication
    
    HTTP or Message Queue
  - PHP Microservice
    
    Use Slim or Lumen
  - Docker Containers
    
    Isolate Each Service
  - Service Registry
    
    Store Service Addresses
  - Circuit Breaker
    
    Handle Service Failures
  - Distributed Tracing
    
    Monitor Request Flow
  - Centralized Logging
    
    Aggregate All Logs
- Message Brokers
  - RabbitMQ Introduction
    
    Message Queue System
  - RabbitMQ PHP Library
    
    php-amqplib Package
  - Producer Code
    
    Send Messages to Queue
  - Consumer Code
    
    Process Queue Messages
  - Exchange Types
    
    Direct Fanout Topic
  - Queue Binding
    
    Connect Exchange to Queue
  - Message Acknowledgment
    
    Confirm Processing
  - Dead Letter Queue
    
    Handle Failed Messages
  - Kafka Introduction
    
    High Throughput Streaming
  - Apache Kafka
    
    Publish Subscribe System
  - RDKafka PHP
    
    Apache Kafka Client
- Webhooks
  - What is Webhook
    
    HTTP Callback on Events
  - Create Webhook Endpoint
    
    Receive POST Requests
  - Verify Webhook Signature
    
    Authenticate Sender
  - Handle Retries
    
    Process Failed Deliveries
  - Idempotency Handling
    
    Prevent Duplicate Processing
  - Event Types List
    
    Payment User Order Events
  - Stripe Webhooks
    
    Payment Events Integration
  - GitHub Webhooks
    
    Code Push Events
  - Webhook Debugging
    
    Use Request Bin
  - Webhook Security
    
    Validate Incoming Requests
- Serverless PHP
  - Bref Introduction
    
    Run PHP on AWS Lambda
  - AWS Lambda
    
    Function as Service
  - Serverless Framework
    
    Deploy PHP Functions
  - API Gateway
    
    HTTP Triggers for Lambda
  - Environment Variables
    
    Configuration in Cloud
  - Cold Start
    
    First Request Delay
  - Database Connection
    
    Use RDS or DynamoDB
  - File Storage
    
    S3 Bucket Integration
  - Cost Optimization
    
    Pay per Execution
  - Local Development
    
    Use Bref Local
- Payment Gateway Integration
  - Stripe Setup
    
    Create Account Get Keys
  - Stripe Checkout
    
    Prebuilt Payment Page
  - Payment Intent API
    
    Create Payment Intent
  - Stripe Webhook
    
    Handle Events
  - Refund Process
    
    Cancel Payment
  - PayPal Setup
    
    REST API Credentials
  - PayPal Orders
    
    Create and Capture
  - Razorpay Setup
    
    Indian Payment Gateway
  - Subscription Billing
    
    Recurring Payments
  - Save Payment Method
    
    Future Charges
- SMS Integration
  - Twilio Setup
    
    Get Account SID Token
  - Send SMS Message
    
    Use Twilio API
  - Verify Phone Number
    
    Send OTP Code
  - Two Factor Authentication
    
    SMS Based Login
  - TextLocal API
    
    Indian SMS Provider
  - Africas Talking
    
    African SMS Gateway
  - Message Queues
    
    Async SMS Sending
  - Bulk SMS Sending
    
    Campaign Management
  - SMS Delivery Status
    
    Webhook for Reports
  - Opt Out Handling
    
    User Unsubscribe Management
- File Format Processing
  - PDF Extraction
    
    Read Text from PDF
  - PDF Creation
    
    Generate Fillable Forms
  - Word Document Processing
    
    Read DOCX Files
  - Excel Advanced Formulas
    
    Read Calculated Values
  - CSV Large Files
    
    Stream Processing
  - ZIP Archive Creation
    
    Compress Multiple Files
  - ZIP Extraction
    
    Unzip Uploaded Files
  - Image EXIF Data
    
    Read Camera Info
  - Barcode Generation
    
    Create QR Codes
  - Markdown Parsing
    
    Convert to HTML
- Data Encryption
  - OpenSSL Extension
    
    Encryption Functions
  - openssl_encrypt
    
    Encrypt Data String
  - openssl_decrypt
    
    Decrypt Encrypted Data
  - AES 256
    
    Strong Encryption Algorithm
  - Encryption Key
    
    Store in Environment
  - IV Initialization Vector
    
    Random Bytes Required
  - Sodium Extension
    
    Modern Cryptography Library
  - sodium_crypto_secretbox
    
    Authenticated Encryption
  - Password Based Encryption
    
    Derive Key from Password
  - Encrypt Database Fields
    
    Sensitive Data Protection
- Data Compression
  - gzcompress
    
    Compress String Data
  - gzuncompress
    
    Decompress String Data
  - gzencode
    
    Create Gzip Content
  - gzdecode
    
    Decode Gzip Data
  - ZipArchive Class
    
    Create ZIP Files
  - Compress Large Files
    
    Stream Compression
  - Compress API Response
    
    Reduce Bandwidth
  - Compress Database Backup
    
    Save Storage Space
  - Compression Level
    
    Balance Speed Size
  - Zstandard Extension
    
    Facebook Compression Algorithm
- Data Serialization
  - serialize Format
    
    PHP Native Serialization
  - unserialize Security
    
    Don't Trust User Input
  - JSON Serialization
    
    Cross Language Compatible