is_a> <get_parent_class
Last updated: Fri, 24 Feb 2012

interface_exists

(PHP 5 >= 5.0.2)

interface_existsCheca se a interface foi definida

Descrição

bool interface_exists ( string $interface_name [, bool $autoload ] )

Verifica se uma interface foi definida.

Parâmetros

interface_name

O nome da interface.

autoload

Se deve chamar __autoload ou não por padrão

Valor Retornado

Essa função retorna TRUE se a interface de nome interface_name já foi definida, FALSE caso contrário.

Exemplos

Exemplo #1 Exemplo de uso de interface_exists()

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

?>

Veja Também



User Contributed Notes
interface_exists
nils dot rocine at gmail dot com
26-Oct-2011 04:35
A little note on namespaces that may be obvious to some, but was not obvious to me.

Although you can make the below statement when the statement is in the same namespace as the interface/class declaration MyInterface...
<?php
$foo
instanceof MyInterface
?>

Making use of the interface_exists, or class_exists functions, you must enter the full namespaced interface name like so (even if the function call is from the same namespace.)
<?php
interface_exists
(__NAMESPACE__ . '\MyInterface', false);
?>
andrey at php dot net
24-Oct-2004 01:40
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.

is_a> <get_parent_class
Last updated: Fri, 24 Feb 2012