The is_a Function
The is_a function takes an object and a class name, returning true if the object is an instance of that class or its descendant. The third parameter can specify whether to consider inheritance (default is true).
Syntax
is_a(object, class_name, allow_string = true);
Example
Let's check if the object belongs to the stdClass class:
<?php
$obj = new stdClass();
var_dump(is_a($obj, 'stdClass'));
?>
Code execution result:
true
Example
Let's check class inheritance:
<?php
class ParentClass {}
class ChildClass extends ParentClass {}
$child = new ChildClass();
var_dump(is_a($child, 'ParentClass'));
?>
Code execution result:
true
Example
Let's check the work with interfaces:
<?php
interface MyInterface {}
class MyClass implements MyInterface {}
$obj = new MyClass();
var_dump(is_a($obj, 'MyInterface'));
?>
Code execution result:
true
See Also
-
the is_subclass_of function,
which checks inheritance -
the instanceof function,
the instance check operator -
the get_class function,
which returns the object's class -
the class_implements function,
which returns the class interfaces
