PHP class_exists function

Like this blog? Consider exploring one of our sponsored banner ads...

class_exists

(PHP 4, PHP 5)

class_exists — Checks if the class has been definedDescriptionbool class_exists ( string class_name [, bool autoload] )

This function checks if the given class have been defined.

Parameters

class_name

The class name

autoload

Whether to call __autoload or not by default


Return Values

Returns TRUE if class_name is a defined class,
FALSE otherwise.

ChangeLog

VersionDescription5.0.0 The autoload was added.


Examples

Example 1. class_exists() example

// Check the class exists before trying to use it
if (class_exists('MyClass')) {
    $myclass = new MyClass();
}

Example 2. autoload parameter example

function __autoload($class)
{
    include($class . '.php');
 
    // Check to see if the include declared the class
    if (!class_exists($class, false)) {
        trigger_error("Unable to load class: $class", E_USER_WARNING);
    }
}
 
if (class_exists('MyClass')) {
    $myclass = new MyClass();
}

See Also

interface_exists()get_declared_classes()


About this entry

You’re currently reading “PHP class_exists function,” an entry on BRADINO

Published:
2.26.07 / 1am
Category:
PHP Functions
Tags: