Edit 4/2018:
The standard OPC UA.Net library runs asynchronously. See Updated Sample.
Edit 9/2016:
Everyone should see the new OPC UA. Standard Standard Library .
You can develop applications that work on all of the common platforms available today, including Linux, iOS, Android (via Xamarin), and Windows.
And you can find many examples, including a sample inspired by this post. Locate the SampleApplications / Samples / NetCoreConsoleClient folder.
Original post:
Help with homework, maybe?
using Opc.Ua; // Install-Package OPCFoundation.NetStandard.Opc.Ua using Opc.Ua.Client; using Opc.Ua.Configuration; using System; using System.Collections.Generic; using System.Diagnostics; using System.Net; namespace MyHomework { class Program { static void Main(string[] args) { Console.WriteLine("Step 1 - Create application configuration and certificate."); var config = new ApplicationConfiguration() { ApplicationName = "MyHomework", ApplicationUri = Utils.Format(@"urn:{0}:MyHomework", System.Net.Dns.GetHostName()), ApplicationType = ApplicationType.Client, SecurityConfiguration = new SecurityConfiguration { ApplicationCertificate = new CertificateIdentifier { StoreType = @"Directory", StorePath = @"%CommonApplicationData%\OPC Foundation\CertificateStores\MachineDefault", SubjectName = Utils.Format(@"CN={0}, DC={1}", "MyHomework", System.Net.Dns.GetHostName()) }, TrustedIssuerCertificates = new CertificateTrustList { StoreType = @"Directory", StorePath = @"%CommonApplicationData%\OPC Foundation\CertificateStores\UA Certificate Authorities" }, TrustedPeerCertificates = new CertificateTrustList { StoreType = @"Directory", StorePath = @"%CommonApplicationData%\OPC Foundation\CertificateStores\UA Applications" }, RejectedCertificateStore = new CertificateTrustList { StoreType = @"Directory", StorePath = @"%CommonApplicationData%\OPC Foundation\CertificateStores\RejectedCertificates" }, AutoAcceptUntrustedCertificates = true, AddAppCertToTrustedStore = true }, TransportConfigurations = new TransportConfigurationCollection(), TransportQuotas = new TransportQuotas { OperationTimeout = 15000 }, ClientConfiguration = new ClientConfiguration { DefaultSessionTimeout = 60000 }, TraceConfiguration = new TraceConfiguration() }; config.Validate(ApplicationType.Client).GetAwaiter().GetResult(); if (config.SecurityConfiguration.AutoAcceptUntrustedCertificates) { config.CertificateValidator.CertificateValidation += (s, e) => { e.Accept = (e.Error.StatusCode == StatusCodes.BadCertificateUntrusted); }; } var application = new ApplicationInstance { ApplicationName = "MyHomework", ApplicationType = ApplicationType.Client, ApplicationConfiguration = config }; application.CheckApplicationInstanceCertificate(false, 2048).GetAwaiter().GetResult(); var selectedEndpoint = CoreClientUtils.SelectEndpoint("opc.tcp://" + Dns.GetHostName() + ":48010", useSecurity: true, operationTimeout: 15000); Console.WriteLine($"Step 2 - Create a session with your server: {selectedEndpoint.EndpointUrl} "); using (var session = Session.Create(config, new ConfiguredEndpoint(null, selectedEndpoint, EndpointConfiguration.Create(config)), false, "", 60000, null, null).GetAwaiter().GetResult()) { Console.WriteLine("Step 3 - Browse the server namespace."); ReferenceDescriptionCollection refs; Byte[] cp; session.Browse(null, null, ObjectIds.ObjectsFolder, 0u, BrowseDirection.Forward, ReferenceTypeIds.HierarchicalReferences, true, (uint)NodeClass.Variable | (uint)NodeClass.Object | (uint)NodeClass.Method, out cp, out refs); Console.WriteLine("DisplayName: BrowseName, NodeClass"); foreach (var rd in refs) { Console.WriteLine("{0}: {1}, {2}", rd.DisplayName, rd.BrowseName, rd.NodeClass); ReferenceDescriptionCollection nextRefs; byte[] nextCp; session.Browse(null, null, ExpandedNodeId.ToNodeId(rd.NodeId, session.NamespaceUris), 0u, BrowseDirection.Forward, ReferenceTypeIds.HierarchicalReferences, true, (uint)NodeClass.Variable | (uint)NodeClass.Object | (uint)NodeClass.Method, out nextCp, out nextRefs); foreach (var nextRd in nextRefs) { Console.WriteLine("+ {0}: {1}, {2}", nextRd.DisplayName, nextRd.BrowseName, nextRd.NodeClass); } } Console.WriteLine("Step 4 - Create a subscription. Set a faster publishing interval if you wish."); var subscription = new Subscription(session.DefaultSubscription) { PublishingInterval = 1000 }; Console.WriteLine("Step 5 - Add a list of items you wish to monitor to the subscription."); var list = new List<MonitoredItem> { new MonitoredItem(subscription.DefaultItem) { DisplayName = "ServerStatusCurrentTime", StartNodeId = "i=2258" } }; list.ForEach(i => i.Notification += OnNotification); subscription.AddItems(list); Console.WriteLine("Step 6 - Add the subscription to the session."); session.AddSubscription(subscription); subscription.Create(); Console.WriteLine("Press any key to remove subscription..."); Console.ReadKey(true); } Console.WriteLine("Press any key to exit..."); Console.ReadKey(true); } private static void OnNotification(MonitoredItem item, MonitoredItemNotificationEventArgs e) { foreach (var value in item.DequeueValues()) { Console.WriteLine("{0}: {1}, {2}, {3}", item.DisplayName, value.Value, value.SourceTimestamp, value.StatusCode); } } } }