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interface_exists

(PHP 5 >= 5.0.2, PHP 7, PHP 8)

interface_exists — Checks if the interface has been defined

Description

interface_exists(string $interface, bool $autoload = true): bool

Checks if the given interface has been defined.

Parameters

interface: The interface name
autoload: Whether to autoload if not already loaded.

Return Values

Returns true if the interface given by interface has been defined, false otherwise.

Examples

Example #1 interface_exists() example

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

?>

See Also

get_declared_interfaces() - Returns an array of all declared interfaces
class_implements() - Return the interfaces which are implemented by the given class or interface
class_exists() - Checks if the class has been defined
enum_exists() - Checks if the enum has been defined

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Licensed under the Creative Commons Attribution License v3.0 or later.
https://www.php.net/manual/en/function.interface-exists.php