Question

Hi I’m calling some items from a web service and when they come back I create an interface tailored to the items returned inside of a seperate method. Now every time in a great while something goes wrong and I need to catch the exception and display a message to the user.

private void itemHelper_FeaturedItemsCalled(object sender, List<MyItem> _myItemList)
{
    try
    {
        Dispatcher.BeginInvoke(() =>
        {
            if(_myItemList != 0)
                CreateInterface(_myItemList);
        });
    }
    catch
    {
        Dispatcher.BeginInvoke(() =>
        {
            LoadingScreen.Visibility = System.Windows.Visibility.Visible;
            LoadingTextBlock.Text = "Unable to display items.";
            BusyIndicator1.IsRunning = false;
        }
    }
}

Now I purposely threw an exception inside the method CreateInterface(). Now when this runs I get and unhandled exception. Why is that? I thought since the method was called inside of the try it would eventually get handled here?

Answer 1

Try putting the try catch inside the BeginInvoke. What is happening is that you are executing this code on a different thread so the exception is not caught by the differing thread.