PHP Function Reference

PHP class_alias() Function



The PHP class_alias() function Creates an alias for a user defined class. The aliased class is exactly the same as the original class.

Syntax

class_alias(class, alias, autoload)

Parameters

class Required. Specify the original class name.
class Required. Specify the alias name for the class.
autoload Optional. Specify whether to call __autoload if the original class is not found.

Return Value

Returns true on success or false on failure.

Example: class_alias() example

The example below shows the usage of class_alias() function.

<?php
class myClass {
  function message() {
    echo "Hello World\n";
  }
}

//creating an alias of the class
class_alias('myClass', 'newClass');

//creating an object
$myObj = new newClass();

//calling method
$myObj->message();
?>

The output of the above code will be:

Hello World

Example: comparing original class and alias class

Consider one more example where the original class is compared with alias class.

<?php
class foo { }

class_alias('foo', 'bar');

$a = new foo();
$b = new bar();

//comparing class objects
var_dump($a == $b, $a === $b);
var_dump($a instanceof $b);

//comparing classes
var_dump($a instanceof foo);
var_dump($a instanceof bar);

var_dump($b instanceof foo);
var_dump($b instanceof bar);
?>

The output of the above code will be:

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

❮ PHP Classes/Objects Reference

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