private extern static int VariantChangeTypeEx([MarshalAs(UnmanagedType.Struct)]out object pvargDest,

Declare Function VariantChangeTypeEx Lib "oleaut32.dll" (TODO) As TODO

     int hr = VariantChangeTypeEx(out Conv, ref OptionValue, Thread.CurrentThread.CurrentCulture.LCID, 0, (short)VarEnum.VT_BSTR);