WPF global exception handler

Question

Sometimes, under not reproducible circumstances, my WPF application crashes without any message. The application simply close instantly.

Where is the best place to implement the global Try/Catch block. At least I have to implement a messagebox with: "Sorry for the inconvenience ..."

Answer 1

You can trap unhandled exceptions at different levels:

1. AppDomain.CurrentDomain.UnhandledException From all threads in the AppDomain.
2. Dispatcher.UnhandledException From a single specific UI dispatcher thread.
3. Application.Current.DispatcherUnhandledException From the main UI dispatcher thread in your WPF application.
4. TaskScheduler.UnobservedTaskException from within each AppDomain that uses a task scheduler for asynchronous operations.

You should consider what level you need to trap unhandled exceptions at.

Deciding between #2 and #3 depends upon whether you're using more than one WPF thread. This is quite an exotic situation and if you're unsure whether you are or not, then it's most likely that you're not.