Question

我在这里使用NetCoreConsoleClient示例：https://github.com/OPCFoundation/UA-.NETStandardLibrary

我自定义了代码并能够浏览整个服务器并为服务器上的每个节点获取时间戳，描述，数据类型等值。

对于节点＆＃34; Channel1.Device1.Tag1＆＃34;我能够获取所有属性/值（如数据类型，地址，描述），但我没有获得保存＆＃34; Tag1＆＃34;

的实际值的属性

在Kepserver上，我注意到＆＃34; Channel1.Device.Tag1＆＃34;没有任何名为＆＃34; Value＆＃34;它包含实际的标签值。

＆＃34; Tag1中＆＃34;当我使用＆＃34;快速客户端＆＃34;由KepServer提供。

我需要取出＆＃34;标签＆＃34;以某种方式使用我自己的客户端。

修改后的代码：

`Console.WriteLine("4 - Browse the OPC UA server namespace.");
        ReferenceDescriptionCollection references;
        Byte[] continuationPoint;

        references = session.FetchReferences(ObjectIds.ObjectsFolder);

        session.Browse(
            null,
            null,
           ObjectIds.ObjectsFolder,
            //ObjectIds.RootFolder,
            0u,
            BrowseDirection.Forward,
            ReferenceTypeIds.HierarchicalReferences,
            true,
            (uint)NodeClass.Variable | (uint)NodeClass.Object | (uint)NodeClass.Method,
            out continuationPoint,
            out references);

        Console.WriteLine(" DisplayName, BrowseName, NodeClass");
        foreach (var rd in references)
        {
            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);
                ReferenceDescriptionCollection nextRefs1;
                byte[] nextCp1;
                session.Browse(
                   null,
                   null,
                   ExpandedNodeId.ToNodeId(nextRd.NodeId, session.NamespaceUris),
                   0u,
                   BrowseDirection.Forward,
                   ReferenceTypeIds.HierarchicalReferences,
                   true,
                   (uint)NodeClass.Variable | (uint)NodeClass.Object | (uint)NodeClass.Method,
                   out nextCp1,
                   out nextRefs1);
                foreach (var nextRd1 in nextRefs1)
                {
                    Console.WriteLine("   + {0}, {1}, {2}", nextRd1.DisplayName, nextRd1.BrowseName, nextRd1.NodeClass);
                    ReferenceDescriptionCollection nextRefs2;
                    byte[] nextCp2;
                   var res =  session.Browse(
                        null, null,
                        ExpandedNodeId.ToNodeId(nextRd1.NodeId, session.NamespaceUris), 0u, BrowseDirection.Forward,
                        ReferenceTypeIds.HierarchicalReferences, true,
                        (uint)NodeClass.Variable | (uint)NodeClass.Object | (uint)NodeClass.Method, out nextCp2, out nextRefs2);
                    double maxAge = 0; //Pick 0 millisecond old value directly from device not from the cache.
                    DataValueCollection results;
                    DiagnosticInfoCollection diagInfos;
                    ReadValueIdCollection readValueIds;
                    foreach (var nextRd2 in nextRefs2)
                    {
                        try
                        {
                            if (!nextRd2.NodeId.IsNull)
                            {
                                var node = ExpandedNodeId.ToNodeId(nextRd2.NodeId, session.NamespaceUris);
                                if (node != null)
                                {
                                    DataValue dv = session.ReadValue(node);
                                    ReferenceDescriptionCollection nextRefs3;
                                    byte[] nextCp3;
                                    var res1 = session.Browse(null, null,
                                           ExpandedNodeId.ToNodeId(nextRd2.NodeId, session.NamespaceUris), 0u, BrowseDirection.Forward,
                                           ReferenceTypeIds.HierarchicalReferences, true,
                                           (uint)NodeClass.Variable | (uint)NodeClass.Object | (uint)NodeClass.Method, out nextCp3, out nextRefs3);
                                    foreach (var nextRd3 in nextRefs3)
                                    {
                                        if (!nextRd3.NodeId.IsNull)
                                        {
                                            var node1 = ExpandedNodeId.ToNodeId(nextRd3.NodeId, session.NamespaceUris);
                                            if (node1 != null)
                                            {
                                                DataValue dv2 = session.ReadValue(node1);
                                            }
                                        }
                                    }
                                }
                            }
                        }
                        catch (ServiceResultException srex)
                        {
                            //eat exception yum yum yum!
                        }
                        catch (Exception ex)
                        {

                            //eat exception yum yum yum!
                        }`

Answer 1

通过对示例代码的点击和试用，我找到了答案。

赋予价值观的神奇陈述是：

DataValue dv1 = session.ReadValue（“ns = 2; s = Channel1.Device1.Tag1”）;

                foreach (var nextRd1 in nextRefs1)
                {
                    Console.WriteLine("   + {0}, {1}, {2}", nextRd1.DisplayName, nextRd1.BrowseName, nextRd1.NodeClass);
                    try
                    {
                        var _node = ExpandedNodeId.ToNodeId(nextRd1.NodeId, session.NamespaceUris);
                        DataValue dv2 = session.ReadValue(_node);
                    }

Answer 2

此示例使用： https://github.com/hylasoft-usa/h-opc#documentation

您可能只需找出需要检索的值类型

public void ReadValueFromOPC(string host, string userName, string password)
    {
        var options = new UaClientOptions
        {
            UserIdentity = new Opc.Ua.UserIdentity(
                userName,
                password)
        };

        using (var client = new UaClient(new Uri("opc.tcp://" +
            host), options))
        {

            client.Connect();
            var node = client.FindNode("SomeTag.SomeChildTag");

            // Find out what the type is before you try to get the value
            Type type = client.GetDataType(node.Tag);
            // If you find out it's a UInt32 then you use it.
            var value = client.Read<UInt32>(node.Tag).Value;

        }
    }

使用OPC UA .NET read＆＃34; Channel1.Device1.Tag1＆＃34;来自Kepserver

2 个答案: