thinkphp如何继承自己的Action

thinkphp怎么继承自己的Action
GlobalAction.class.php

PHP code

<!--Code highlighting produced by Actipro CodeHighlighter (freeware)http://www.CodeHighlighter.com/-->class GlobalAction extends Action{  public function _initialize()  {  }}

IndexAction.class.php

PHP code

<!--Code highlighting produced by Actipro CodeHighlighter (freeware)http://www.CodeHighlighter.com/-->class IndexAction extends GlobalAction{}

我这么写结果报错，说GlobalAction没有找到

------解决方案--------------------
class IndexAction extends GlobalAction之前，GlobalAction.class.php必须被加载进来，不然肯定会报错的。
------解决方案--------------------
include(__APP__/lib/GlobalAction.class.php)