Ищем пример для асинхронной загрузки файла с помощью объекта flex filereference
Это то, что вы ищете:
http://blog.flexexamples.com/2007/09/21/uploading-files-in-flex-using-the-filereference-class/
В случае разрыва связи:
<?xml version="1.0" encoding="utf-8"?> <!-- http://blog.flexexamples.com/2007/09/21/uploading-files-in-flex-using-the-filereference-class/ --> <mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="vertical" verticalAlign="middle" backgroundColor="white" creationComplete="init();"> <mx:Script> <![CDATA[ private var fileRef:FileReference; private const FILE_UPLOAD_URL:String = "http://www.YOUR-WEBSITE-HERE.com/fileref/uploader.cfm"; private function init():void { fileRef = new FileReference(); fileRef.addEventListener(Event.SELECT, fileRef_select); fileRef.addEventListener(ProgressEvent.PROGRESS, fileRef_progress); fileRef.addEventListener(Event.COMPLETE, fileRef_complete); } private function browseAndUpload():void { fileRef.browse(); message.text = ""; } private function fileRef_select(evt:Event):void { try { message.text = "size (bytes): " + numberFormatter.format(fileRef.size); fileRef.upload(new URLRequest(FILE_UPLOAD_URL)); } catch (err:Error) { message.text = "ERROR: zero-byte file"; } } private function fileRef_progress(evt:ProgressEvent):void { progressBar.visible = true; } private function fileRef_complete(evt:Event):void { message.text += " (complete)"; progressBar.visible = false; } ]]> </mx:Script> <mx:NumberFormatter id="numberFormatter" /> <mx:Button label="Upload file" click="browseAndUpload();" /> <mx:Label id="message" /> <mx:ProgressBar id="progressBar" indeterminate="true" visible="false" /> </mx:Application>