Hi Siw

Sounds like you're missing a <form runat="server"> around your content in your master-template in order to make this work - could you perhaps post a snippet of what your master template looks like?

/Jan

Hi there Jan, excuse me for responding late. I'm back at the case now. 
I'm not missing a form runat=server tag. It's not in the master template as several of the subtemplates have need of such a tag.
I've made a simple user control that reports data from subnodes of a doctype node with the pdcalendar attached. The report control contains a gridview and I've put it in a small template on a separat reporting page. It works fine until I click the button that renders the gridview to a stream with content type application/vnd.ms-excel.
Then I get this:

Server Error in '/' Application.

Control 'ContentPlaceHolderDefault_tmpMainContentPlaceHolder_RapportKursdeltakere_3_gvRapport' of type 'GridView' must be placed inside a form tag with runat=server.

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. 

Exception Details: System.Web.HttpException: Control 'ContentPlaceHolderDefault_tmpMainContentPlaceHolder_RapportKursdeltakere_3_gvRapport' of type 'GridView' must be placed inside a form tag with runat=server.

Source Error: 

Stack Trace: 

[HttpException (0x80004005): Control 'ContentPlaceHolderDefault_tmpMainContentPlaceHolder_RapportKursdeltakere_3_gvRapport' of type 'GridView' must be placed inside a form tag with runat=server.]
   System.Web.UI.Page.VerifyRenderingInServerForm(Control control) +11271910
   System.Web.UI.WebControls.GridView.Render(HtmlTextWriter writer, Boolean renderPanel) +75
   kbrKurs.RapportKursdeltakere.btnExcel_Click(Object sender, EventArgs e) +725
   System.Web.UI.WebControls.Button.RaisePostBackEvent(String eventArgument) +154
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +3691

Version Information: Microsoft .NET Framework Version:4.0.30319; ASP.NET Version:4.0.30319.1 

After reading your answer I tried moving the server side form tag from around the macro in the report template and into the ascx form itself. It didn't make any differende. 

The code of the click event: 

protected void btnExcel_Click(object sender, EventArgs e)

{
            Response.ClearContent();
            Response.ContentType = "application/vnd.ms-excel";
            Response.AddHeader("Content-Disposition", "attachment; filename=Kursdeltakere_" + DateTime.Today.ToShortDateString() + ".xls");
            Response.ContentEncoding = System.Text.Encoding.Unicode;
            Response.BinaryWrite(System.Text.Encoding.Unicode.GetPreamble());

            StringBuilder sb = new StringBuilder();
            StringWriter tw = new StringWriter(sb);
            HtmlTextWriter hw = new HtmlTextWriter(tw);

            gvRapport.RenderControl(hw);
            Response.Write(sb);
            Response.End();
        }

}

So I've tried the usual remedy: putting in an override f the verifyRenderingInServerForm. But when I do this in my VS project it won't compile, the error is:

Error1'kbrKurs.RapportKursdeltakere.VerifyRenderingInServerForm(System.Web.UI.Control)': no suitable method found to overrideC:\Users\Siw\PROSJEKTER\KBR\kbrKurs\kbrKurs\RapportKursdeltakere.ascx.cs14330kbrKurs

Did you ever get this resolved?  I'm facing a similar issue when trying to export to PDF.  

Thanks.

Sean

No, I'm sorry, I convinced my customer he could live without it, I didn't have more time to spend on the issue.

But I sure would like know how to handle this - good luck!

Siw

HA HA!  Nice.

Basically what I ended up doing was build out the html "manually".  I was trying to get the html from a gridview to be able to send that to a PDF.  The error forced me into a corner to where I had to come up with something.  It's not optimal, by any stretch, but it gets us by.

I appreciate your response.

Thanks.

Sean

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