PHP 手冊
上一頁 |  | 下一頁

# 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 ( object 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.

示範 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";
}
// Outputs "yes, $WFC is a subclass of WidgetFactory\n";
if (is_subclass_of($WF, 'WidgetFactory')) {
echo "yes, \$WF is a subclass of WidgetFactory\n";
} else {
echo "no, \$WF is not a subclass of WidgetFactory\n";
}
// Outputs "no, $WF is not a subclass of WidgetFactory\n"
?>`

See also get_class(), get_parent_class() and is_a().

上一頁 | 最開頭 | 下一頁
is_a | 上一層 | method_exists