How can code in a "try...catch" block throw an unhandled exception?

Question

I had an exception in some code today: "A [some exception] was unhandled."

However, this code was clearly inside the "try" block of a "try/catch" structure.

What am I missing here?

Update: It's C#

Update: Oh, forget it. It turns out the specific mechanism of error is that I'm an idiot. There's no fix for this.

Answer 1

Does the catch statement specify a specific type of exception?

If it does, it will only catch that type of exception.

Answer 2

Were you running in a debugger with "break on exceptions"/"break on thrown" switched on? In this case you'll see the exception before it is passed to the try/catch.

Answer 3

I have 10 dollars that says its a ThreadAbortException or some other self-throwing exception. If that is the case you must catch the exception twice.

Answer 4

Without knowing the language it's difficult to say, but many languages have the concept of exceptions that cannot be caught - for example in .NET, OutOfMemoryException and ExecutionEngineException (amongst others) cannot be caught, since they are essentially non-recoverable.

Answer 5

some problems caused by Recursion such as StackOverFlow exceptions and the like will throw inside of try...catch blocks because they are not actually thrown from any particular line of code within the block, but rather by the CLR. This is also true for Memory out of range exceptions and other problems that aren't the direct result of any one line of code.

Maybe you're talking about something like this:

Answer 6

Unmanaged exceptions will not be caught by catch(Exception e),you can try a

    try
    {
    }
    catch
    {
    }

instead of

        try
        {
        }
        catch (Exception e)
        {
        }