/// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
        }
 
        private void ClientOnMonitoredItemChanged(object sender, EasyUAMonitoredItemChangedEventArgs eventArgs)
        {
            // We have passed in a reference to the target TextBox as the State property in EasyUAMonitoredItemArguments.
            var textBox = (TextBox) eventArgs.Arguments.State;
 
            if (eventArgs.Succeeded)
                textBox.Text = eventArgs.AttributeData.DisplayValue();
            else
                textBox.Text = "*** Error";
        }
 
        private void Window_Loaded(object sender, RoutedEventArgs e)
        {
            // Define the target controls, the OPC data we want to monitor, and how fast.
            var arguments = new []
            {
                new EasyUAMonitoredItemArguments(TextBox1, "http://localhost:51211/UA/SampleServer", "nsu=http://test.org/UA/Data/;i=10845", 1000),
                new EasyUAMonitoredItemArguments(TextBox2, "http://localhost:51211/UA/SampleServer", "nsu=http://test.org/UA/Data/;i=10853", 1000),
                new EasyUAMonitoredItemArguments(TextBox3, "http://localhost:51211/UA/SampleServer", "nsu=http://test.org/UA/Data/;i=10855", 1000)
            };
 
            // Hook the event handler, and subscribe to OPC data
            _client.MonitoredItemChanged += ClientOnMonitoredItemChanged;
            _handles = _client.SubscribeMultipleMonitoredItems(arguments);
        }
 
        private void Window_Unloaded(object sender, RoutedEventArgs e)
        {
            // Unsubscribe from OPC data, and unhook the event handler
            _client.UnsubscribeMultipleMonitoredItems(_handles);
            _client.MonitoredItemChanged -= ClientOnMonitoredItemChanged;
        }
 
        private readonly EasyUAClient _client = new EasyUAClient();
 
        private int[] _handles;
    }