is_subclass_of

Checks if the object has this class as one of its parents or implements it

bool **is_subclass_of** mixed $object_or_class string $class bool $allow_string

Checks if the given has the class as one of its parents or implements it. object_or_class``class

object_or_classA class name or an object instance. No error is generated if the class does not exist.

classThe class name

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

This function returns true if the object , belongs to a class which is a subclass of , false otherwise. object_or_class``class

Voorbeeld: 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";
}


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";
}
?>

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

Voorbeeld: using interface example

<?php
// Define the Interface
interface MyInterface
{
  public function MyFunction();
}

// Define the class implementation of the interface
class MyClass implements MyInterface
{
  public function MyFunction()
  {
    return "MyClass Implements MyInterface!";
  }
}

// Instantiate the object
$my_object = new MyClass;

// Works since 5.3.7

// Test using the object instance of the class
if (is_subclass_of($my_object, 'MyInterface')) {
  echo "Yes, \$my_object is a subclass of MyInterface\n";
} else {
  echo "No, \$my_object is not a subclass of MyInterface\n";
}

// Test using a string of the class name
if (is_subclass_of('MyClass', 'MyInterface')) {
  echo "Yes, MyClass is a subclass of MyInterface\n";
} else {
  echo "No, MyClass is not a subclass of MyInterface\n";
}
?>

Yes, $my_object is a subclass of MyInterface
Yes, MyClass is a subclass of MyInterface

get_class``get_parent_class``is_a``class_parents

Vorige ← is_a Volgende method_exists →

is_subclass_of

is_subclass_of

Documentatie