flash删除所有子元素避免内存泄露

public static function removeAllChildren(container:DisplayObjectContainer):void{
			try{
				var child:DisplayObject;
				for (var i:Number = container.numChildren - 1; i >= 0; i--) {
					child = container.getChildAt(i);
					if (child is DisplayObjectContainer && !(child is Loader/*跨域引用图片时，子元素不允许访问，否则报沙箱安全移除*/)) {
						
						removeAllChildren(DisplayObjectContainer(child));
					}
					container.removeChild(child);
				}
			}catch(e:Error){
				Alert.show("Util.removeAllChildren异常:"+e);
			}
}