public override void Start()
        {
            if (!device.enable)
            {
                return;
            }
            IntPtr            error     = new IntPtr();
            IntPtr            param     = new IntPtr();
            NET_DEVICEINFO_EX stDevInfo = new NET_DEVICEINFO_EX();

            lLoginHandle = CLIENT_LoginEx2(device.ip, (UInt16)device.port, device.user, device.pwd, 0, param, ref stDevInfo, error);
            if (lLoginHandle != 0)
            {
                if (CLIENT_StartListenEx(lLoginHandle))
                {
                    OnConnectEH(device, 0);
                }
            }
            else
            {
                OnConnectEH(device, 1);
            }

            if (!listInstrument.Contains(this))
            {
                listInstrument.Add(this);
            }
        }
 private static extern int CLIENT_LoginEx2(string pchDVRIP, UInt16 wDVRPort, string pchUserName, string pchPassword, int mode, IntPtr param, ref NET_DEVICEINFO_EX lpDeviceInfo, IntPtr error);