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class_implements

(PHP 5, PHP 7, PHP 8)

class_implements 返回指定的类或接口实现的所有接口

说明

class_implements(object|string $object_or_class, bool $autoload = true): array|false

本函数返回数组,包含指定 object_or_class 及其父类所实现的所有接口的名称。

参数

object_or_class

对象(类实例)或字符串(类名或接口名)。

autoload

如果尚未加载,是否自动加载

返回值

成功时为数组,当指定类不存在则为 false

示例

示例 #1 class_implements() 示例

<?php

interface foo { }
class
bar implements foo {}

print_r(class_implements(new bar));

// 可以指定参数为字符串
print_r(class_implements('bar'));

spl_autoload_register();

// 使用自动加载去加载“not_loaded”类
print_r(class_implements('not_loaded', true));

?>

以上示例的输出类似于:

Array
(
    [foo] => foo
)
Array
(
    [foo] => foo
)
Array
(
    [interface_of_not_loaded] => interface_of_not_loaded
)

注释

注意: 检测对象是否 implements interface,应该使用 instanceofis_a() 函数。

参见

add a note

User Contributed Notes 4 notes

up
15
ludvig dot ericson at gmail dot nospam dot com
18 years ago
Hint:
<?php
in_array
("your-interface", class_implements($object_or_class_name));
?>
would check if 'your-interface' is ONE of the implemented interfaces.
Note that you can use something similar to be sure the class only implements that, (whyever you would want that?)
<?php
array("your-interface") == class_implements($object_or_class_name);
?>

I use the first technique to check if a module has the correct interface implemented, or else it throws an exception.
up
10
a dot panek at brainsware dot org
10 years ago
Calling class_implements with a non-loadable class name or a non-object results in a warning:

<?php
// Warning: class_implements(): Class abc does not exist and could not be loaded in /home/a.panek/Projects/sauce/lib/Sauce/functions.php on line 196

$interfaces = class_implements('abc');
?>

This is not documented and should just return FALSE as the documentation above says.
up
3
trollll23 at yahoo dot com
18 years ago
Luckily, it prints out superinterfaces as well in reverse order so iterative searching works fine:

<?php

interface InterfaceA { }

interface
InterfaceB extends InterfaceA { }

class
MyClass implements InterfaceB { }

print_r(class_implements(new MyClass()));

?>

prints out:

Array
(
[InterfaceB] => InterfaceB
[InterfaceA] => InterfaceA
)
up
-12
sam at rmcreative dot ru
4 years ago
The order of interfaces is not reliable and varies between PHP versions.
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