Question

How do one create a COMException given a HRESULT?

I have P/Invoke:ed a win32-method which returns a HRESULT.
If it returns failure I wish to throw a COMException, with the standard error-text.
How should I do that?

1. throw new COMException(null, hResult)

2. COMException e = new COMException;
e.HResult = hResult;
throw e;

Or should I use some other method?

Answer 1

You should use Marshal.GetExceptionForHR() if you only want to get the exception, or Marshal.ThrowExceptionForHR() if want to throw it too.