Question

Ok what id like to do is to load a page that displays 90% of content, and load the last 10% asynchronously.

As im rendering the page i programatically create an update panel which i pass to a thread. When this thread finishes it then updates the updatepanel on the main thread.

public void test(object parameter)
{
    Thread.Sleep(2000);
    var updpanel = (UpdatePanel)parameter;
    updpanel.ContentTemplateContainer.Controls.Add(new LiteralControl("HI"));
    updpanel.Update();
}
protected void Page_Load(object sender, EventArgs e)
{
    var th = new Thread(new ParameterizedThreadStart(test));
    var updpanel = new UpdatePanel() { UpdateMode = UpdatePanelUpdateMode.Conditional };
    ContentPlaceHolder1.Controls.Add(updpanel);
    th.Start(updpanel);
}

Failing this, in a single threaded approach, do i just keep polling the page to see if it has finished or not?

Answer 1

You cannot use threading this way on the server. Your second thread will probably not complete until after the page have been processed and the request lifecycle is complete.

Depending on what you are trying to achieve: do you need to process data in parallel server-side you should look into Asynchronous Pages in ASP.Net 2.0.

Another approach would be to render the page (“90%” as you call it) and use ajax on the client to request additional data.