private void Application_UnhandledException(object sender, ApplicationUnhandledExceptionEventArgs e) {
     // If the app is running outside of the debugger then report the exception using
     // a ChildWindow control.
     if (!System.Diagnostics.Debugger.IsAttached) {
         // NOTE: This will allow the application to continue running after an exception has been thrown
         // but not handled. 
         // For production applications this error handling should be replaced with something that will 
         // report the error to the website and stop the application.
         e.Handled = true;
         ChildWindow errorWin = new ErrorWindow(e.ExceptionObject);
         errorWin.Show();
     }
 }
 // If an error occurs during navigation, show an error window
 private void ContentFrame_NavigationFailed(object sender, NavigationFailedEventArgs e) {
     e.Handled = true;
     ChildWindow errorWin = new ErrorWindow(e.Uri);
     errorWin.Show();
 }