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
Parameters
object_or_class-
A class name or an object instance.
class-
The class or interface name
allow_string-
If this parameter is set to false, a string class name as object_or_class
is not allowed. This also prevents calling the 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';
}
?>
interface_exists
Classes/Object Functions