flash as3.0 怎么添加超链接Url

function GoToURL(event:MouseEvent)
{
 var url = new URLRequest("http://www.zzzyk.com");
 navigateToURL(url)
}

url_button.addEventListener(MouseEvent.MOUSE_DOWN, GoToURL);
url_button.buttonMode = true;useHandCursor="true" buttonMode="true"

function gotoMyUrl(event:MouseEvent):void{
   var myUrl:URLRequest = new URLRequest("http://www.hzhuti.com")
   navigateToURL(myUrl,"_self");
}

//场景中新建一个按钮，实例名为my_button;为按钮添加侦听器(就是把函数应用到按钮上，使其被按钮控制)

btn1.addEventListener(MouseEvent.CLICK, gotoMyUrl);