Handling an unhandled exception

If a .NET exception goes unhandled, the process crashes with an unpleasant dialog presented to the user by Windows. Unpleasantness aside, the user may lose data as a result of the crash.

WPF provides a way to catch unhandled exceptions and perhaps handle them in some meaningful way. At the very least, the application may present a friendlier looking crash report and perhaps write the exception information to some log. At best, the application may recover from the error and continue running normally. Let's see how this can be done.

Getting ready

Make sure Visual Studio is up and running.

How to do it...

We'll create a simple application that throws an unhandled exception and see how we can catch it even if it's unhandled:

1. Create a new WPF Application project named CH05.UnhandledExceptions.

2. Open MainWindow.xaml. Add a Button to the Grid as follows:

   <Button Content="Throw Exception" FontSize="20" Margin="10" />

3. Add a Click handler to the button. In the handler...