Language Reference

• Basic syntax
  • Instruction separation
  • Comments
• Types
  • Booleans
  • Integers
  • Floating point numbers
  • Strings
  • Arrays
  • Objects
  • Resources
  • NULL
  • Pseudo-types and variables used in this documentation
  • Type Juggling
• Variables
  • Predefined variables
  • Variable scope
  • Variable variables
  • Variables from outside PHP
• Constants
  • Magic constants
• Expressions
• Operators
  • Arithmetic Operators
  • Assignment Operators
  • Bitwise Operators
  • Comparison Operators
  • Error Control Operators
  • Execution Operators
  • Incrementing/Decrementing Operators
  • Logical Operators
  • String Operators
  • Array Operators
  • Type Operators
• Control Structures
  • if
  • else
  • elseif
  • Alternative syntax for control structures
  • while
  • do-while
  • for
  • foreach
  • break
  • continue
  • switch
  • declare
  • return
  • require
  • include
  • require_once
  • include_once
• Functions
  • Function arguments
  • Returning values
  • Variable functions
  • Internal (built-in) functions
• Classes and Objects (PHP 4)
  • extends
  • Constructors
  • Scope Resolution Operator (::)
  • parent
  • Serializing objects - objects in sessions
  • The magic functions __sleep and __wakeup
  • References inside the constructor
  • Comparing objects
• Classes and Objects (PHP 5)
  • The Basics
  • Autoloading Objects
  • Constructors and Destructors
  • Visibility
  • Scope Resolution Operator (::)
  • Static Keyword
  • Class Constants
  • Class Abstraction
  • Object Interfaces
  • Overloading
  • Object Iteration
  • Patterns
  • Magic Methods
  • Final Keyword
  • Object cloning
  • Comparing objects
  • Reflection
  • Type Hinting
  • Late Static Bindings
• Namespaces
  • Namespace definition
  • Using namespaces
  • Global space
  • __NAMESPACE__
  • Name resolution rules
• Exceptions
• References Explained
  • What References Do
  • What References Are Not
  • Passing by Reference
  • Returning References
  • Unsetting References
  • Spotting References
• Predefined variables
  • Superglobals — Superglobals are built-in variables that are always available in all scopes
  • $GLOBALS — References all variables available in global scope
  • $_SERVER — Server and execution environment information
  • $_GET — HTTP GET variables
  • $_POST — HTTP POST variables
  • $_FILES — HTTP File Upload variables
  • $_REQUEST — HTTP Request variables
  • $_SESSION — Session variables
  • $_ENV — Environment variables
  • $_COOKIE — HTTP Cookies
  • $php_errormsg — The previous error message
  • $HTTP_RAW_POST_DATA — Raw POST data
  • $http_response_header — HTTP response headers
  • $argc — The number of arguments passed to script
  • $argv — Array of arguments passed to script
• Predefined Exceptions
  • Exception
  • ErrorException
• Context options and parameters
  • Socket context options — Socket context option listing
  • HTTP context options — HTTP context option listing
  • FTP context options — FTP context option listing
  • SSL context options — SSL context option listing
  • CURL context options — CURL context option listing
  • Context parameters — Context parameter listing