is_a

(PHP 4 >= 4.2.0, PHP 5, PHP 7, PHP 8)

is_a — Checks whether the object is of a given type or subtype

Description

is_a(mixed $object_or_class, string $class, bool $allow_string = false): bool

Determines if the given object_or_class is the class object type, or has class as one of its supertypes.

Parameters

object_or_class

A class name or an object instance.

class

The class or interface name

allow_string

If this parameter set to false, string class name as object_or_class is not allowed. This also prevents from calling autoloader if the class doesn't exist.

Return Values

Returns true if object_or_class is the class object type, or has class as one of its supertypes, false otherwise.

Examples

Example #1 is_a() example

<?php
// define a class
class WidgetFactory
{
var $oink = 'moo';
}

// create a new object
$WF = new WidgetFactory();

if (is_a($WF, 'WidgetFactory')) {
echo "yes, \$WF is still a WidgetFactory\n";
}
?>

Example #2 Using the instanceof operator

<?php
// define a class
class WidgetFactory
{
var $oink = 'moo';
}

// create a new object
$WF = new WidgetFactory();

if ($WF instanceof WidgetFactory) {
echo 'Yes, $WF is a WidgetFactory';
}
?>

See Also