How to do C++ style destructors in C#?

Question

I've got a C# class with a Dispose function via IDisposable. It's intended to be used inside a using block so the expensive resource it handles can be released right away.

The problem is that a bug occurred when an exception was thrown before Dispose was called, and the programmer neglected to use using or finally.

In C++, I never had to worry about this. The call to a class's destructor would be automatically inserted at the end of the object's scope. The only way to avoid that happening would be to use the new operator and hold the object behind a pointer, but that required extra work for the programmer isn't something they would do by accident, like forgetting to use using.

Is there any way to for a using block to be automatically used in C#?

Many thanks.

UPDATE:

I'd like to explain why I'm not accepting the finalizer answers. Those answers are technically correct in themselves, but they are not C++ style destructors.

Here's the bug I found, reduced to the essentials...

try
{
    PleaseDisposeMe a = new PleaseDisposeMe();
    throw new Exception();
    a.Dispose();
}
catch (Exception ex)
{
    Log(ex);
}

// This next call will throw a time-out exception unless the GC
// runs a.Dispose in time.
PleaseDisposeMe b = new PleaseDisposeMe();

Using FXCop is an excellent suggestion, but if that's my only answer, my question would have to become a plea to the C# people, or use C++. Twenty nested using statements anyone?

Answer 1

Unfortunately there isn't any way to do this directly in the code. If this is an issue in house, there are various code analysis solutions that could catch these sort of problems. Have you looked into FxCop? I think that this will catch these situations and in all cases where IDisposable objects might be left hanging. If it is a component that people are using outside of your organization and you can't require FxCop, then documentation is really your only recourse :).

Edit: In the case of finalizers, this doesn't really guarantee when the finalization will happen. So this may be a solution for you but it depends on the situation.