C# rethrow an exception: how to get the exception stack in the IDE?

The debugger breaks at the throw in Main because that exception is unhandled. By default, the debugger will only break on unhandled exceptions. Once you've stopped at Main, the call stack for the original exception from foo is present in the exception, but all of the other context has been lost (e.g. locals, stack/memory state).

It sounds like you want the debugger to break on the throw in foo, so you should tell the debugger to break on first-chance exceptions:

1. Debug » Exceptions... (Ctrl+Alt+E)
2. Check "Thrown" for the exception types you care about (in this case, Commange Language Runtime Exceptions)
3. Click OK
4. Start debugging

In this case, the debugger will break immediately when foo throws an exception. Now, you can examine the stack, locals, etc., in the context of the original exception. If you continue execution (F5), the debugger will break again on the rethrow in Main.

Taking another approach, if you're running VS2010 Ultimate, you can also use IntelliTrace to "debug backwards" to see parameters, threads, and variables at the time of the exception. See this MSDN article for details. (Full disclosure: I work on a team closely related to IntelliTrace).

If you use ReSharper, you can copy exception stacktrace to clipboard, then choose in the menu: ReSharper > Tools > Browse Stack Trace (Ctrl+E,T). It will show stacktrace with clickable locations, so you'll be able to quickly navigate.

_{(source: jetbrains.com)}

This feature is also very useful while digging through logs from users (if stacktraces of exceptions are logged).