}       

        }       

       

        // called after the file is opened before upload   

        private function openHandler(event:Event):void{

            trace('openHandler triggered');

            _files;

        }

       

        // called during the file upload of each file being uploaded | we use this to feed the progress bar its data

        private function progressHandler(event:ProgressEvent):void {       

            _progressbar.setProgress(event.bytesLoaded,event.bytesTotal);

            _progressbar.label = "Uploading " + Math.round(event.bytesLoaded / 1024) + " kb of " + Math.round(event.bytesTotal / 1024) + " kb " + (_files.length - 1) + " files remaining";

        }

        // called after a file has been successully uploaded | we use this as well to check if there are any files left to upload and how to handle it

        private function completeHandler(event:Event):void{

            //trace('completeHanderl triggered');

            _files.removeItemAt(0);

            if (_files.length > 0){

                _totalbytes = 0;

                uploadFiles(null);

            }else{

                setupCancelButton(false);

                 _progressbar.label = "Uploads Complete";

                 var uploadCompleted:Event = new Event(Event.COMPLETE);

                dispatchEvent(uploadCompleted);

            }

        }   

         

        // only called if there is an  error detected by flash player browsing or uploading a file  

        private function ioErrorHandler(event:IOErrorEvent):void{

            //trace('And IO Error has occured:' +  event);

            mx.controls.Alert.show(String(event),"ioError",0);

        }   

        // only called if a security error detected by flash player such as a sandbox violation

        private function securityErrorHandler(event:SecurityErrorEvent):void{

            //trace("securityErrorHandler: " + event);

            mx.controls.Alert.show(String(event),"Security Error",0);

        }

       

        //  This function its not required

        private function cancelHandler(event:Event):void{

            // cancel button has been clicked;

            trace('cancelled');

        }

       

        //  after a file upload is complete or attemted the server will return an http status code, code 200 means all is good anything else is bad.

        private function httpStatusHandler(event:HTTPStatusEvent):void {

        //        trace("httpStatusHandler: " + event);

            if (event.status != 200){

                mx.controls.Alert.show(String(event),"Error",0);

            }

        }

       

    }

}

上传工具了，非常好用，大家试试吧.