Question

I am using the following event to catch unhandled exceptions in the main UI thread.

Application.ThreadException 

Unfortunately, it does not catch those unhandled errors in seperate threads. I am aware of

AppDomain.CurrentDomain.UnhandledException

However, this seems to shut down the application upon triggering, where as the former does not.

Is there a way to deal with unhandled exceptions on separate threads, without the application closing?

Answer 1

@Ani have already answered your question. Although I don’t agree that unhandled exceptions in threads should terminate applications. Using threads usually means that you have some kind of server application. Bringing it down could result in a lot of angry users.

I’ve written a small piece about proper exception handling: https://coderr.io/exception-handling

You should always catch exceptions for threads. I usually use the following pattern:

  void ThreadMethod(object state)
  {
      try
      {
          ActualWorkerMethod();
      }
      catch (Exception err)
      {
          _logger.Error("Unhandled exception in thread.", err);
      }
  }

  void ActualWorkerMethod()
  {
      // do something clever
  }

It’s a whole lot easier to find thread methods that doesn’t handle exceptions properly by moving the logic into a seperate method and just keep the try/catch block in the thread method.