URLLoader非常简单封装

非常简单的URLLoader封装，支持参数和回调函数，默认POST。

public static function HttpRequest(url:String, parms:Array, callback:Function):void{            var _request:URLRequest = new URLRequest(url);            var _vars:URLVariables = new URLVariables();            var _loader:URLLoader;            var i:int;                       for (i = 0; i < parms.length;i++ ){                _vars[parms[i][0]] = parms[i][1];            }            _request.method = URLRequestMethod.POST;            _request.data = _vars;                        _loader = new URLLoader(_request);            _loader.addEventListener(Event.COMPLETE, callback);            _loader.load(_request);        }