Should event handlers in C# ever raise exceptions?

Question

As a general rule, are there ever any circumstances in which it\'s acceptable for a method responsible for listening to an event to throw an exception (or allow to be thrown

Answer 1

The only two types of exceptions that should come out of events are serious, potentially process-ending ones like System.OutOfMemoryException or System.DllNotFoundException, and things that are clearly programming errors, like System.StackOverflowException or System.InvalidCastException. Catching and dropping these kinds of exceptions is never a good idea -- let them float up to the top and let the developer decide what to do with them on an application level.

As for the rest... any common or garden-variety exception like System.IO.IOException should be handled inside your event, and you should have some mechanism for returning such error conditions to the caller.