private static async Task TestAsync() { var discoveryUrl = "opc.tcp://*****:*****@"%LOCALAPPDATA%\Workstation.ConsoleApp\pki")), userIdentity, remoteEndpoint)) { try { await session.OpenAsync(); } catch (ServiceResultException ex) { if ((uint)ex.HResult == StatusCodes.BadSecurityChecksFailed) { Console.WriteLine("Error connecting to endpoint. Did the server reject our certificate?"); } throw ex; } Console.WriteLine("Step 5 - Browse the server namespace."); Console.WriteLine("+ Root"); BrowseRequest browseRequest = new BrowseRequest { NodesToBrowse = new BrowseDescription[] { new BrowseDescription { NodeId = NodeId.Parse(ObjectIds.RootFolder), BrowseDirection = BrowseDirection.Forward, ReferenceTypeId = NodeId.Parse(ReferenceTypeIds.HierarchicalReferences), NodeClassMask = (uint)NodeClass.Variable | (uint)NodeClass.Object | (uint)NodeClass.Method, IncludeSubtypes = true, ResultMask = (uint)BrowseResultMask.All } }, }; BrowseResponse browseResponse = await session.BrowseAsync(browseRequest); foreach (var rd1 in browseResponse.Results[0].References ?? new ReferenceDescription[0]) { Console.WriteLine(" + {0}: {1}, {2}", rd1.DisplayName, rd1.BrowseName, rd1.NodeClass); browseRequest = new BrowseRequest { NodesToBrowse = new BrowseDescription[] { new BrowseDescription { NodeId = ExpandedNodeId.ToNodeId(rd1.NodeId, session.NamespaceUris), BrowseDirection = BrowseDirection.Forward, ReferenceTypeId = NodeId.Parse(ReferenceTypeIds.HierarchicalReferences), NodeClassMask = (uint)NodeClass.Variable | (uint)NodeClass.Object | (uint)NodeClass.Method, IncludeSubtypes = true, ResultMask = (uint)BrowseResultMask.All } }, }; browseResponse = await session.BrowseAsync(browseRequest); foreach (var rd2 in browseResponse.Results[0].References ?? new ReferenceDescription[0]) { Console.WriteLine(" + {0}: {1}, {2}", rd2.DisplayName, rd2.BrowseName, rd2.NodeClass); browseRequest = new BrowseRequest { NodesToBrowse = new BrowseDescription[] { new BrowseDescription { NodeId = ExpandedNodeId.ToNodeId(rd2.NodeId, session.NamespaceUris), BrowseDirection = BrowseDirection.Forward, ReferenceTypeId = NodeId.Parse(ReferenceTypeIds.HierarchicalReferences), NodeClassMask = (uint)NodeClass.Variable | (uint)NodeClass.Object | (uint)NodeClass.Method, IncludeSubtypes = true, ResultMask = (uint)BrowseResultMask.All } }, }; browseResponse = await session.BrowseAsync(browseRequest); foreach (var rd3 in browseResponse.Results[0].References ?? new ReferenceDescription[0]) { Console.WriteLine(" + {0}: {1}, {2}", rd3.DisplayName, rd3.BrowseName, rd3.NodeClass); } } } Console.WriteLine("Press any key to continue..."); Console.ReadKey(true); Console.WriteLine("Step 6 - Create a subscription."); var subscriptionRequest = new CreateSubscriptionRequest { RequestedPublishingInterval = 1000, RequestedMaxKeepAliveCount = 10, RequestedLifetimeCount = 30, PublishingEnabled = true }; var subscriptionResponse = await session.CreateSubscriptionAsync(subscriptionRequest).ConfigureAwait(false); var id = subscriptionResponse.SubscriptionId; Console.WriteLine("Step 7 - Add items to the subscription."); var itemsToCreate = new MonitoredItemCreateRequest[] { new MonitoredItemCreateRequest { ItemToMonitor = new ReadValueId { NodeId = NodeId.Parse("i=2258"), AttributeId = AttributeIds.Value }, MonitoringMode = MonitoringMode.Reporting, RequestedParameters = new MonitoringParameters { ClientHandle = 12345, SamplingInterval = -1, QueueSize = 0, DiscardOldest = true } } }; var itemsRequest = new CreateMonitoredItemsRequest { SubscriptionId = id, ItemsToCreate = itemsToCreate, }; var itemsResponse = await session.CreateMonitoredItemsAsync(itemsRequest).ConfigureAwait(false); Console.WriteLine("Step 8 - Publish the subscription."); var publishRequest = new PublishRequest { SubscriptionAcknowledgements = new SubscriptionAcknowledgement[0] }; Console.WriteLine("Press any key to delete the subscription..."); while (!Console.KeyAvailable) { var publishResponse = await session.PublishAsync(publishRequest).ConfigureAwait(false); // loop thru all the data change notifications var dcns = publishResponse.NotificationMessage.NotificationData.OfType <DataChangeNotification>(); foreach (var dcn in dcns) { foreach (var min in dcn.MonitoredItems) { Console.WriteLine($"clientHandle: {min.ClientHandle}; value: {min.Value}"); } } publishRequest = new PublishRequest { SubscriptionAcknowledgements = new[] { new SubscriptionAcknowledgement { SequenceNumber = publishResponse.NotificationMessage.SequenceNumber, SubscriptionId = publishResponse.SubscriptionId } } }; } Console.ReadKey(true); Console.WriteLine("Step 9 - Delete the subscription."); var request = new DeleteSubscriptionsRequest { SubscriptionIds = new uint[] { id } }; await session.DeleteSubscriptionsAsync(request).ConfigureAwait(false); Console.WriteLine("Press any key to close the session..."); Console.ReadKey(true); Console.WriteLine("Step 10 - Close the session."); await session.CloseAsync(); } }