var fileRef:FileReference = new FileReference();
		var request:URLRequest = new URLRequest(serviceUrl);

		request.method = URLRequestMethod.POST;
		var encoder : Base64Encoder = new Base64Encoder();
		encoder.encode(userName + ":" + password);
		request.requestHeaders.push(new URLRequestHeader("Authorization", "Basic " + encoder.toString())); // ** 增加认证信息

		fileRef.addEventListener(Event.OPEN, onFileDownloadBegin);
		fileRef.addEventListener(Event.COMPLETE, onFileDownloadComplete);
		fileRef.addEventListener(IOErrorEvent.IO_ERROR, onFileDownloadError);
		fileRef.addEventListener(Event.CANCEL, onFileDownLoadCancel);
		fileRef.download(request, getExportFileName(serviceUrl));

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