How to correctly unwrap a TargetInvocationException?

Question

I am writing a component which, at the top level, invokes a method via reflection. To make my component easier to use, I'd like to catch any exceptions thrown by the invoked method and unwrap them.

Thus, I have something like:

try { method.Invoke(obj, args); }
catch (TargetInvocationException ex) {
    throw ex.InnerException;
}

However, this blows away the inner exception stack trace. I can't use just throw here (because I'm rethrowing a different exception object). What can I do in my catch block to make sure that the original exception type, message, and stack trace all get through?

No need to place tags in your question title. Tagging correctly is sufficient. — spender, Jul 09 '13 at 18:19
Why do you think it makes it easier to confuse the stack trace? — John Saunders, Jul 09 '13 at 18:58

score 34 · Accepted Answer · edited May 23 '17 at 12:17

34

As answered here, starting with .NET 4.5 you can use the ExceptionDispatchInfo class to unwrap the inner exception.

try
{
    someMethod.Invoke();
}
catch(TargetInvocationException ex)
{
    ExceptionDispatchInfo.Capture(ex.InnerException).Throw();
}

edited May 23 '17 at 12:17

Community

1
1

answered Oct 10 '14 at 15:29

Dusty

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Should be marked as the answer. Had the same problem and it was driving me crazy. – Zwirbelbart Mar 14 '16 at 17:02

How to correctly unwrap a TargetInvocationException?

1 Answers1