Response.End() generates an error when exporting gridview to excel file

Question

I have this code:

protected void ibtGenerateReport_Click(object sender, ImageClickEventArgs e)
{
    string filename = "report.xls";             

    StringWriter stringWriter = new StringWriter();
    HtmlTextWriter htmlWrite = new HtmlTextWriter(stringWriter);
    DataGrid DataGrd = new DataGrid();            
    DataGrd.DataSource = odsLSRAudit;
    DataGrd.DataBind();

    DataGrd.RenderControl(htmlWrite);            

    System.IO.StreamWriter vw = new System.IO.StreamWriter(filename, true);
    stringWriter.ToString().Normalize();
    vw.Write(stringWriter.ToString());
    vw.Flush();
    vw.Close();
    WriteAttachment(filename, "application/vnd.ms-excel", stringWriter.ToString());           
}

public static void WriteAttachment(string FileName, string FileType, string content)
{
    HttpResponse Response = System.Web.HttpContext.Current.Response;
    Response.ClearHeaders();
    Response.AppendHeader("Content-Disposition", "attachment; filename=" + FileName);
    Response.ContentType = FileType;
    Response.Write(content);            
    Response.End();
}

But the Response.End() gives me the below error:

Microsoft JScript runtime error: Sys.WebForms.PageRequestManagerParserErrorException: The message received from the server could not be parsed. Common causes for this error are when the response is modified by calls to Response.Write(), response filters, HttpModules, or server trace is enabled. Details: Error parsing near '<table cellspacing="'.

The Response.Write(content) has the correct information as I can see. But no Save/Open dialog box appear, besides the above error.

I'm using UpdatePanels.

are you using updatepanels or asp.net ajax? try this http://stackoverflow.com/questions/11221033/sys-webforms-pagerequestmanagerparsererrorexception-the-message-received-from-t — feco, Feb 18 '13 at 17:39

feco · Accepted Answer · 2015-07-21T16:43:55.533

Add this to your Page_Load() method

Assuming ibtGenerateReport is your button

protected void Page_Load(object sender, EventArgs e) {
   ScriptManager scriptManager = ScriptManager.GetCurrent(this.Page);
   scriptManager.RegisterPostBackControl(this.ibtGenerateReport);
   //Further code goes here....
}

Explanation:

The UpdatePanel control uses asynchronous postbacks to control which parts of the page get rendered. It does this using a whole bunch of JavaScript on the client and a whole bunch of C# on the server. This is rendered out using a special format that the JavaScript on the client can understand. If you mess with the format by rendering things outside of the render phase of the page, the format will be messed up.

Why do I keeping getting a PageRequestManagerParserErrorException?

Well, chances are you're doing one of the things mentioned in the error message. Here are the most common reasons and why they don't work:

Calls to Response.Write(): By calling Response.Write() directly you are bypassing the normal rendering mechanism of ASP.NET controls. The bits you write are going straight out to the client without further processing.

Response filters /HttpModules : Similar to Response.Write(), they can change the rendering in such a way that the UpdatePanel won't know.

Server trace is enabled: Trace is effectively written out using Response.Write(), and as such messes up the special format that we use for UpdatePanel.

Calls to Server.Transfer(): Unfortunately, there's no way to detect that Server.Transfer() was called. This means that UpdatePanel can't do anything intelligent when someone calls Server.Transfer(). The response sent back to the client is the HTML markup from the page to which you transferred. Since its HTML and not the special format, it can't be parsed, and you get the error.

Solution: One way to avoid the parse error is to do a regular postback instead of an asynchronous postback by calling ScriptManager.RegisterPostBackControl()

Please refer to the complete Explanation and other solutions from Ellon Lipton's blog here

Try to export your gridview using this tutorial http://ramanisandeep.net/2009/04/07/export-gridview-to-excel/ — feco, Feb 18 '13 at 17:52

score 4 · Answer 2 · answered Feb 18 '13 at 17:40

Change Response.End by this:

Response.Flush();
HttpContext.Current.ApplicationInstance.CompleteRequest();

Response.End is a bad practice, it aborts the thread to bypass the rest of the operations in the http request lifecycle and it throws an exception.

score 0 · Answer 3 · answered Feb 18 '13 at 17:37

0

Have you tried a Response.Clear() prior to writing anything to the response, then a Response.Flush() before ending the response?

Also, it never hurts to pass a value of true in Response.End(), to avoid HTTP exception errors on a redirect. Just make sure the rest of the code-behind isn't doing additional processing you don't want.

answered Feb 18 '13 at 17:37

Ripside

145
2
8

I didn't notice he was using Update Panels - the Clear() isn't needed in that case. – Ripside Feb 18 '13 at 17:46

score 0 · Answer 4 · answered Feb 18 '13 at 17:48

Since you are trying to do it through UpdatePanels, you should try using jQuery Ajax and write this code in a separate page in the page load event to get the file when you invoke the request to this page. The new response is actually removing the information required to be parsed as a response to the previous update panel request.

score 0 · Answer 5 · answered Mar 29 '16 at 07:00

0

This code is conflicting some UpdatePanel/AJAX in your aspx.

Try writing this in your aspx:

Code - which should work! :')

answered Mar 29 '16 at 07:00

SBelim

3
1

Response.End() generates an error when exporting gridview to excel file

5 Answers5