is_subclass_of
(PHP 4 , PHP 5)
is_subclass_of --
Returns
TRUE if the object has this class as one of its parents
Description
bool
is_subclass_of ( mixed object, string class_name)
This function returns TRUE if the object
object, belongs to a class which is a
subclass of class_name, FALSE otherwise.
Note:
Since PHP 5.0.3 you may also specify the object
parameter as a string (the name of the class).
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 get_class(),
get_parent_class() and
is_a().