How to Avoid Response.End() "Thread was being aborted" Exception during the Excel file download

Question

I tried to convert my dataset into excel and download that excel .I got my required excel file.But System.Threading.ThreadAbortException was raised every excel download. How to resolve this issue ?.. Please help me...

I call this method in my aspx screen.There also same exception has thrown by this method.

I call that public void ExportDataSet(DataSet ds) function in many aspx screens and also I am maintaining error logger method for exceptions which are raised at runtime right those exceptions are write into a .txt files. So that same exception is logged in all the aspx screen's txt files.I just want to avoid this exception throws from method declared class file to aspx. Simply i just want to handle this exception at my method declaration class file itself.

ASPX File Method call: excel.ExportDataSet(dsExcel);

Method Definition:

public void ExportDataSet(DataSet ds)
{

   try
   {
      string filename = "ExcelFile.xls";
      HttpResponse response = HttpContext.Current.Response;
      response.Clear();
      response.Charset = "";
      response.ContentType = "application/vnd.ms-excel";
      response.AddHeader("Content-Disposition", "attachment;filename=\"" + filename + "\"");
      using (StringWriter sw = new StringWriter())
      {
         using (HtmlTextWriter htw = new HtmlTextWriter(sw))
         {
             GridView dg = new GridView();
             dg.DataSource = ds.Tables[0];
             dg.DataBind();
             dg.RenderControl(htw);
             // response.Write(style);
             response.Write(sw.ToString());                                                
             response.End();                    // Exception was Raised at here
         }
      }
   }
   catch (Exception ex)
   {
      string Err = ex.Message.ToString();
      EsHelper.EsADLogger("HOQCMgmt.aspx ibtnExcelAll_Click()", ex.Message.ToString());
   }
   finally
   {                
   }
}

Answer 1

I researched online and saw that the Response.End() always throws an exception.

Replace this: HttpContext.Current.Response.End();

With this:

HttpContext.Current.Response.Flush(); // Sends all currently buffered output to the client.
HttpContext.Current.Response.SuppressContent = true;  // Gets or sets a value indicating whether to send HTTP content to the client.
HttpContext.Current.ApplicationInstance.CompleteRequest(); // Causes ASP.NET to bypass all events and filtering in the HTTP pipeline chain of execution and directly execute the EndRequest event.

Answer 2

This helped me to handle Thread was being aborted exception,

try
{
   //Write HTTP output
    HttpContext.Current.Response.Write(Data);
}  
catch (Exception exc) {}
finally {
   try 
    {
      //stop processing the script and return the current result
      HttpContext.Current.Response.End();
     } 
   catch (Exception ex) {} 
   finally {
        //Sends the response buffer
        HttpContext.Current.Response.Flush();
        // Prevents any other content from being sent to the browser
        HttpContext.Current.Response.SuppressContent = true;
        //Directs the thread to finish, bypassing additional processing
        HttpContext.Current.ApplicationInstance.CompleteRequest();
        //Suspends the current thread
        Thread.Sleep(1);
     }
   }

if you use the following the following code instead of HttpContext.Current.Response.End() , you will get Server cannot append header after HTTP headers have been sent exception.

            HttpContext.Current.Response.Flush();
            HttpContext.Current.Response.SuppressContent = True;
            HttpContext.Current.ApplicationInstance.CompleteRequest();

Hope it helps

Answer 3

Move the Response.End() to outside of the Try/Catch and Using blocks.

It's suppose to throw an Exception to bypass the rest of the request, you just weren't suppose to catch it.

bool endRequest = false;

try
{
    .. do stuff
    endRequest = true;
}
catch {}

if (endRequest)
    Resonse.End();