public static void Main()
{
	using (var easyAEClient = new EasyAEClient())
	{
		var eventHandler = new EventHandler<EasyAENotificationEventArgs>(easyAEClient_Notification);
		easyAEClient.Notification += eventHandler;
 
		int handle = easyAEClient.SubscribeEvents("", "OPCLabs.KitEventServer.2", 1000);
 
		Console.WriteLine("Processing event notifications for 1 minute...");
		Thread.Sleep(60 * 1000);
 
		easyAEClient.UnsubscribeEvents(handle);
	}
}
 
// Notification event handler
static void easyAEClient_Notification([NotNull] object sender, [NotNull] EasyAENotificationEventArgs e)
{
	if (e.Event != null) 
		Console.WriteLine(e.Event.Message);
}

public static EasyUAClient EasyUAClientInstance = new EasyUAClient()
{
	Isolated = true,
	IsolatedParameters =
	{
		Session =
		{
			CertificateAcceptancePolicy = { AcceptAnyCertificate = true, AllowUserAcceptCertificate = false },
			EndpointSelectionPolicy =
			{
				AllowedMessageSecurityModes = UAMessageSecurityModes.SecurityNone,
				EnforceSameSite = true
			},
			UserIdentity =
			{
				// Valori di default sovrascritti dopo
				UserNameTokenInfo = { UserName = "gst", Password = "pw" }
			},
			SelectBestEndpoint = true,
			// Valori di default sovrascritti dopo
			SessionConnectTimeout = 20000
		},
	}
};
 
/*
	serverURLAddress = opc.tcp://test.domainServer.com
	port = 4123
*/
 
private static bool InstanziateEasyUAClient(string serverURLAddress, int port,
											int sessionConnectTimeout, int threadRefreshMillisec,
											string userName, string password)
{
	bool ok = false;
	int millisectoHoldOPCUAConnection = threadRefreshMillisec;
	try
	{
		#region Assegnazione Parametri da configurazione
		EasyUAClientInstance.IsolatedParameters.Session.UserIdentity.UserNameTokenInfo
			= new UserNameTokenInfo()
			{
				UserName = userName,
				Password = password
			};
		// Segue parametro: Tempo entro il quale NON VERRA' FATTO LogOut e si manterrà la connessione (aumentato del 60%)
		millisectoHoldOPCUAConnection = millisectoHoldOPCUAConnection + (int)Math.Ceiling(millisectoHoldOPCUAConnection * 0.6);
		EasyUAClientInstance.IsolatedParameters.Session.HoldPeriod = millisectoHoldOPCUAConnection;
		if (sessionConnectTimeout > 0)
		{
			EasyUAClientInstance.IsolatedParameters.Session.SessionTimeout = sessionConnectTimeout;
		}
		m_ServerURLEasyUAClient = string.Format("{0}:{1}", serverURLAddress, port);
		#endregion
 
		// Event Handler di tutto quel che accade nell'interazione col Server OPC UA
		EasyUAClient.LogEntry += EasyUAClient_LogEntry;
		ok = true;
	}
	catch (Exception ex)
	{
		ok = false;
		m_logger.Error("InstanziateEasyUAClient() '{0}'\r\n" +
						"Other info: serverURLAddress= '{1}', OPCUA SessionTimeOut = '{2}', OPCUA HoldPeriod = '{3}'\r\n{4}\r\n",
						ex.Message, serverURLAddress + ":" + port, sessionConnectTimeout, millisectoHoldOPCUAConnection, ex.StackTrace);
	}
	return ok;
}
 
// using  the   EasyUAClientInstance:
 
	UANodeId nodeId = new UANodeId(CommonNamespaceURIString, strNodeIdIdentifier); 
// Where:   CommonNamespaceURIString="http://domainServer.com/UAComServer/"
//          strNodeIdIdentifier = "IMO1234567/Meteorology/Wind/Angle";
    UANodeElementCollection nodeElementCollection = EasyUAClientInstance.BrowseDataNodes(MainUAEndpointDescriptor, nodeId);
// Where:    MainUAEndpointDescriptor="opc.tcp://test.domainServer.com:4123"
 
	UANodeElementCollection nodeElementCollection = EasyUAClientInstance.BrowseDataNodes(MainUAEndpointDescriptor, nodeId);

using OpcLabs.EasyOpc.UA;
using OpcLabs.EasyOpc.UA.AddressSpace;
using OpcLabs.EasyOpc.UA.OperationModel;
 
//... etc
bool okSubscription = StartSubscribe(strNodeIdIdentifier, Heading_ItemChanged);
// ... etc
 
private static bool StartSubscribe(string strNodeIdIdentifier, EasyUAMonitoredItemChangedEventHandler callBackMethodHandler)
{
	bool ok = true;
	UANodeId nodeId = new UANodeId("http://urlAddress.com/UAComServer/", "IMO1234567/NavigationalData/AIS");
	object state = null;
	int[] handleArray = OPCUACore.EasyUAClientInstance.SubscribeMultipleMonitoredItems(new[]
        {
            new EasyUAMonitoredItemArguments(callBackMethodHandler, 
                                            state, 
                                            "opc.tcp:ServerUrlAddress.com:4321", 
                                            nodeId, 
                                            m_configParams.MillisecSampleInterval) 
        });
	return ok;
}
// This is an Example of Event Handler for change
private static void Heading_ItemChanged(object sender, EasyUAMonitoredItemChangedEventArgs e)
{            
    // ...
    try
    {
        if (e.Exception != null)
        {
            // An error to log
        }
        else
        {
            // some previous operation
            UAAttributeData item = e.AttributeData;
            fullInfoItemValue = e.AttributeData.ToString();
            itemValue = e.AttributeData.Value.ToString();
            lastUpdateUTC = e.AttributeData.SourceTimestamp;
 
            if (!string.IsNullOrEmpty(itemValue)
                && Monitor.TryEnter(ShipData.Instance.nauticalInfo, new TimeSpan(0, 0, 2)))
            {
                try
                {
                    ShipData.Instance.nauticalInfo.heading.SetValue(double.Parse(itemValue), m_configParams.SourceName, lastUpdateUTC);
                }
                catch (Exception ex)
                {
                    // Error to log
                }
                finally
                {
                    Monitor.Exit(ShipData.Instance.nauticalInfo);
                }
            }            
        }
    }
    catch (Exception ex)
    {
        // Error to log
    }
}