Programmatically exporting report to Excel directly from Web App

[Jill]

When opening a report in xlsx using Q1'12 controls, this is throwing an error:  Thread was being aborted.  It then prompts me to open or save it, then says "it couldn't be downloaded".  But when I click "retry" it opens fine in excel as xlsx.

Here is my code: 

var reportProcessor = new Telerik.Reporting.Processing.ReportProcessor();
                Telerik.Reporting.Processing.RenderingResult result = reportProcessor.RenderReport("xlsx", reportToExport, null);

                string fileName = reportName + ".xlsx";
                Response.Clear();
                Response.Charset = "";
                Response.ContentType = "application/vnd.xlsx";
                Response.Cache.SetCacheability(HttpCacheability.Private);
                Response.Expires = -1;
                Response.Buffer = false;
                Response.AddHeader("Content-Disposition",string.Format("{0};FileName=\"{1}\"", "attachment", fileName));
                Response.OutputStream.Write(result.DocumentBytes, 0, result.DocumentBytes.Length);
                Response.End();

[Steve]

Hello Jill,

We have not been able to reproduce any problems with your code and the latest Q2 internal build. So our recommendation is to upgrade to the latest version and change your code like this to see if you would still be having problems:

void ExportReport(Telerik.Reporting.Report reportToExport)
       {
           Telerik.Reporting.InstanceReportSource instanceReportSource = new Telerik.Reporting.InstanceReportSource();
           instanceReportSource.ReportDocument = reportToExport;
           ReportProcessor reportProcessor = new ReportProcessor();
           RenderingResult result = reportProcessor.RenderReport("XLSX", instanceReportSource, null);

           string fileName = result.DocumentName + "." + result.Extension;

           Response.Clear();
           Response.ContentType = result.MimeType;
           Response.Cache.SetCacheability(HttpCacheability.Private);
           Response.Expires = -1;
           Response.Buffer = true;

           Response.AddHeader("Content-Disposition",
                              string.Format("{0};FileName=\"{1}\"",
                                            "attachment",
                                            fileName));

           Response.BinaryWrite(result.DocumentBytes);
           Response.End();
       }

Regards,
Steve
the Telerik team

[David]

I encountered the same strange behavior when writing XLSX files to an HTTP response (in a plain ASP.net website, not a Telerik product). When I called Response.End() the "Thread was being aborted" exception was thrown.

This behavior was strange in that if I wrote a XLS file in the same way, it was not a problem. This is not specific to Sitefinity or Telerik. I was able to fix my problem by removing the "Response.End()" call and let the response end on it's own. Others on the internet have encourntered this error by a Server.Transfer or a Response.Redirect. Others catch the ThreadAbortException and swallow the error, and just move on.

Anyhow, I am hoping others may benefit from this, as I found this thread while researching my own problem.

~DavB