protected unsafe void EnableActionSetStateVariables()
        {
            iCallbackSetStateVariables = new CallbackSetStateVariables(DoSetStateVariables);
            IntPtr ptr = GCHandle.ToIntPtr(iGch);

            DvServiceUpnpOrgAVTransport2EnableActionSetStateVariables(iHandle, iCallbackSetStateVariables, ptr);
        }
 static extern void DvServiceUpnpOrgAVTransport2EnableActionSetStateVariables(uint aHandle, CallbackSetStateVariables aCallback, IntPtr aPtr);