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interface_exists

(PHP 5 >= 5.0.2)

interface_exists -- Checks if the interface has been defined

Description

bool interface_exists ( string interface_name [, bool autoload] )

This function returns TRUE if the interface given by interface_name has been defined, FALSE otherwise.

例子 1. interface_exists() example

<?php
// Check the interface exists before trying to use it
if (interface_exists('MyInterface')) {
    class MyClass implements MyInterface
    {
        // Methods
    }
}

?>

interface_exists() will attempt to call __autoload by default, if you don't want interface_exists() to call __autoload, you can set the parameter autoload to FALSE.

See also class_exists().


add a note add a note User Contributed Notes
andrey at php dot net
24-Oct-2004 07:40
As far as I remember interface_exists() was added in 5.0.2 . In 5.0.0 and 5.0.1 class_exists() used to return TRUE when asked for a existing interface. Starting 5.0.2 class_exists() doesn't do that anymore.
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