AjaxControlToolkit.AjaxFileUpload.UploadRequestProcessor.XhrStart C# (CSharp) Method

            void XhrStart()
            {
                var filesInQueue = int.Parse(Request.QueryString["queue"] ?? "0");
                var args = new AjaxFileUploadStartEventArgs(filesInQueue);
                if(UploadStart != null)
                    UploadStart(this, args);
                Response.Write(new JavaScriptSerializer().Serialize(args));
            }