Question

I have a asp.net 2.0 web app which calls a long running stored proc (about 3 minutes). The sp actually performs many tasks on the backend.

My page uses threading and ajax (update panel) and a timer control to dispaly a progess bar to the user. This all works great unless there is an error in the sp which just freezes the screen.

I have tried useing a SafeThread class which I found on codeProject which wraps the thread process and creates an event which can be handled in the case of an exception.

In the event handler I just want to redirect the user to an error page and display an error. When testing I can break in the event handler. Calling either Server.Transfer or Response.Redirect however, has no effect at all.

I am not sure why this happenning. I will post my code below. Any ideas or alternative suggestions appreciated.

    protected void btnSave_OnClick(object sender, EventArgs e)     {         DAC dac = new DAC();         Session['RerunStatus'] = 0;         SafeThread thrd = new SafeThread(new ParameterizedThreadStart(dac.RerunTest));         thrd.IsBackground = true;          //tell the SafeThread to report          //ThreadAbort exceptions         thrd.ShouldReportThreadAbort = true;         //attach a ThreadException handler for          //reporting SafeThread exceptions         thrd.ThreadException += new         ThreadThrewExceptionHandler(thrd_ThreadException);          thrd.Start(ddlRundate.SelectedItem.Text);         Session['RerunThread'] = thrd;         btnSave.Enabled = false;         Timer1.Enabled = true;     }      void thrd_ThreadException(SafeThread thrd, Exception ex)     {         //thrd.Abort();         Timer1.Enabled = false;         //Response.Redirect('ErrorPage.aspx');         Server.Transfer('ErrorPage.aspx?ErrorMsg=' + ex.Message);         //thrd.Abort();     } 

Answer 1

You can only use Server.Transfer()/Response.Redirect() when handling a request – that is not the case when your thrd_ThreadException() get’s called.

Try to set a flag in your thrd_ThreadException and do the redirect in the Timer1 Tick event.