Classes/Objects
PHP Manual

is_subclass_of

(PHP 4, PHP 5)

is_subclass_of — Checks if the object has this class as one of its parents

Description

bool is_subclass_of ( mixed $object , string $class_name )

Checks if the given object has the class class_name as one of its parents.

Parameters

object

A class name or an object instance

class_name

The class name

Return Values

This function returns TRUE if the object object , belongs to a class which is a subclass of class_name , FALSE otherwise.

ChangeLog

Version Description
5.0.3 You may also specify the object parameter as a string (the name of the class)

Examples

Example#1 is_subclass_of() example

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

// define a child class
class WidgetFactory_Child extends WidgetFactory
{
  var 
$oink 'oink';
}

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

if (
is_subclass_of($WFC'WidgetFactory')) {
  echo 
"yes, \$WFC is a subclass of WidgetFactory\n";
} else {
  echo 
"no, \$WFC is not a subclass of WidgetFactory\n";
}


if (
is_subclass_of($WF'WidgetFactory')) {
  echo 
"yes, \$WF is a subclass of WidgetFactory\n";
} else {
  echo 
"no, \$WF is not a subclass of WidgetFactory\n";
}


// usable only since PHP 5.0.3
if (is_subclass_of('WidgetFactory_Child''WidgetFactory')) {
  echo 
"yes, WidgetFactory_Child is a subclass of WidgetFactory\n";
} else {
  echo 
"no, WidgetFactory_Child is not a subclass of WidgetFactory\n";
}
?>

The above example will output:

yes, $WFC is a subclass of WidgetFactory no, $WF is not a subclass of WidgetFactory yes, WidgetFactory_Child is a subclass of WidgetFactory

See Also


Classes/Objects
PHP Manual