private void TestExt() { WMUtils.WMCheckURLExtension(@"c:\foo.wmv"); try { WMUtils.WMCheckURLExtension(@".fjfjjjfjjfjfjfjjjfjjf"); Debug.Assert(false); } catch (Exception e) { int hr = Marshal.GetHRForException(e); Debug.Assert(hr == NSResults.E_INVALID_NAME); } }