public static extern HRESULT PropVariantChangeType(Ole32.PROPVARIANT ppropvarDest, [In] Ole32.PROPVARIANT propvarSrc, PROPVAR_CHANGE_FLAGS flags, ushort vt);
public static extern HRESULT PropVariantChangeType([Out] PROPVARIANT ppropvarDest, [In] PROPVARIANT propvarSrc, PROPVAR_CHANGE_FLAGS flags, VARTYPE vt);