PHP Manual: Creates an alias for a class

Description

bool class_alias(string $class, string $alias, bool $autoload = true)

Creates an alias named alias based on the user defined class class. The aliased class is exactly the same as the original class.

Note: As of PHP 8.3.0, class_alias also supports creating an alias of a PHP internal class.

Parameters

class: The original class.
alias: The alias name for the class.
autoload: Whether to autoload if the original class is not found.

Return Values

Returns true on success or false on failure.

Changelog

Version	Description
8.3.0	class_alias now supports creating an alias of an internal class.

Examples

Example #1 class_alias example

<?php

class Foo { }

class_alias('Foo', 'Bar');

$a = new Foo;
$b = new Bar;

// the objects are the same
var_dump($a == $b, $a === $b);
var_dump($a instanceof $b);

// the classes are the same
var_dump($a instanceof Foo);
var_dump($a instanceof Bar);

var_dump($b instanceof Foo);
var_dump($b instanceof Bar);

?>

The above example will output:

bool(true)
bool(false)
bool(true)
bool(true)
bool(true)
bool(true)
bool(true)

Notes

Note:
Class names are case-insensitive in PHP, and this is reflected in this function. Aliases created by class_alias are declared in lowercase. This means that for a class MyClass, the class_alias('MyClass', 'MyClassAlias') call will declare a new class alias named myclassalias.

class_alias