public static void MainSubScription() { UAEndpointDescriptor endpointDescriptor = "opc.tcp://localhost:4840"; // Instantiate the client object and hook events. var client = new EasyUAClient(); client.EventNotification += client_EventNotification; Console.WriteLine("Subscribing..."); client.SubscribeEvent(endpointDescriptor, UAObjectIds.Server, 1000); Console.WriteLine("Processing event notifications for 30 seconds..."); //System.Threading.Thread.Sleep(30 * 1000); Console.WriteLine("Unsubscribing..."); //client.UnsubscribeAllMonitoredItems(); Console.WriteLine("Waiting for 5 seconds..."); //System.Threading.Thread.Sleep(5 * 1000); Console.WriteLine("Finished."); } private static void client_EventNotification(object sender, EasyUAEventNotificationEventArgs e) { // Display the event. if (e.EventData is null) { Console.WriteLine(e.ErrorMessage); return; } Console.WriteLine("All fields:"); foreach (KeyValuePair<UAAttributeField, ValueResult> pair in e.EventData.FieldResults) { UAAttributeField attributeField = pair.Key; ValueResult valueResult = pair.Value; Console.WriteLine(" {0} -> {1}", attributeField, valueResult); } }