public MainPage()
        {
            InitializeComponent();

            txtDeviceManufacturer.Text = DeviceExtendedProperties.GetValue("DeviceManufacturer").ToString();
            txtDeviceName.Text         = DeviceExtendedProperties.GetValue("DName").ToString();

            _svc = new CalculatorServiceProxy.Service1Client();
            _svc.AddCompleted += (s, e) =>
            {
                txtAnswer.Text = e.Result.ToString();
            };
        }
        public MainPage()
        {
            InitializeComponent();

            txtDeviceManufacturer.Text = DeviceExtendedProperties.GetValue("DeviceManufacturer").ToString();
            txtDeviceName.Text         = DeviceExtendedProperties.GetValue("DeviceName").ToString();

            _svc = new CalculatorServiceProxy.Service1Client();
            _svc.AddCompleted += (s, e) =>
            {
                if (e.Error == null)
                {
                    txtAnswer.Text = e.Result.ToString();
                }
                else
                {
                    MessageBox.Show(string.Format("CalculatorService return an error {0}", e.Error.Message));
                }
            };
        }