请教AS3 如何限制重复加载
第一帧：

JScript code

stop();var dx=loaderInfo.parameters["dx"];var uFlash="";if (dx) {    uFlash=dx;}//this['parent']['parent'].subCallMain();var loader = new Loader();loader.load (new URLRequest(uFlash+"wel_banner1.swf"));loader.contentLoaderInfo.addEventListener(Event.COMPLETE,onCompleteEvent);function onCompleteEvent(e:Event):void{    weizhi.addChild(loader); }

第二帧：

JScript code

stop();loader.load (new URLRequest(uFlash+"wel_banner2.swf"));loader.contentLoaderInfo.addEventListener(Event.COMPLETE,onCompleteEvent);

第三帧：

JScript code

stop();loader.load (new URLRequest(uFlash+"wel_banner3.swf"));loader.contentLoaderInfo.addEventListener(Event.COMPLETE,onCompleteEvent);

现在的问题是：有三个按钮，当点击时，跳到不同的帧，按钮单击两次会出现SWF被addChild两次，怎样才不会出现两次？求解答，谢谢



[解决办法]
最好改变下思路，用AS3编程，就不要再把动作放在帧上了吧？

frame 1

JScript code

stop();var dx=loaderInfo.parameters["dx"];var uFlash="";if (dx) {    uFlash=dx;}//this['parent']['parent'].subCallMain();var loader = new Loader();loader.contentLoaderInfo.addEventListener(Event.COMPLETE,onCompleteEvent);function onCompleteEvent(e:Event):void{    weizhi.addChild(loader); }var flag:Array;if(!flag){    flag = new Array(0,0,0);}if(flag[0]==0){    flag[0]=1;    loader.load (new URLRequest(uFlash+"wel_banner1.swf"));}