How should OOB Silverlight 4 app show unhandled errors to UI? (HtmlPage)

Question

I have a SL OOB app (it only runs OOB) and was wondering about the ReportErrorToDOM code in the app.xaml.css:

From what I understand, HtmlPage wont work in OOB as there is no DOM/HTML? Is that why this code is wrapped in a TryCatch block? (this is the default for a new SL4 app).

To get my OOB app to display unhandled errors to the UI, should I judt replace the HTMLPage with a MessageBox.Show?

I can't find anything on Google about this, opinions appreciated...

  private void ReportErrorToDOM(ApplicationUnhandledExceptionEventArgs e)
    {
        try
        {
            string errorMsg = e.ExceptionObject.Message + e.ExceptionObject.StackTrace;
            errorMsg = errorMsg.Replace('"', '\'').Replace("\r\n", @"\n");

            System.Windows.Browser.HtmlPage.Window.Eval("throw new Error(\"Unhandled Error in Silverlight Application " + errorMsg + "\");");
        }
        catch (Exception)
        {
        }
    }

score 1 · Accepted Answer · answered Dec 17 '10 at 08:11

As an initial starting position yes you should replace the code with code that uses MessageBox.Show to display the error.

What is appropriate for a production quality release will depend on the type of application. Strictly speaking if your application has encountered an unhandled exception it would be in an indeterminate state so a message box and/or the replacing of the root visual might make sense.

If its a game then simply swallowing the error might even be appropriate or just noting it in some log.

Thanks for your advice Anthony. I'll probably log the error and show something basic in the MessageBox. — Rodney, Dec 19 '10 at 21:21

score 0 · Answer 2 · answered Dec 30 '10 at 19:25

Take a look at the Silverlight Navigation Application template in VS - it uses a ChildWindow to show errors, and this works OOB as well. You could just generate a dummy project from this template and copy/paste most of the code over to your app to get going quickly, then tweak the UI to suit your needs.

How should OOB Silverlight 4 app show unhandled errors to UI? (HtmlPage)

2 Answers2