使用OPC UA .NET读“Channel1.Device1.Tag1”从Kepserver
问题描述:
值我使用从这里NetCoreConsoleClient样本:https://github.com/OPCFoundation/UA-.NETStandardLibrary使用OPC UA .NET读“Channel1.Device1.Tag1”从Kepserver
我定制的代码,并能够通过整个服务器浏览和取像时间戳值,描述,数据类型等,用于服务器上的每个节点。
结点“Channel1.Device1.Tag1”我能够获取所有属性/ vlaues(如数据类型,地址,说明),但我没有得到这举办“Tag1中”
的实际值的属性在Kepserver上,我注意到对于“Channel1.Device.Tag1”,没有任何名称为“Value”的属性保存了实际的标签值。
当我使用KepServer提供的“快速客户端”时,出现“Tag1”值。
我需要使用我自己的客户端以某种方式获取“标签”值。
改性一段代码:
`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!
}`
答
通过
命中和试验样品上的代码,我发现了答案。
其给出的值的神奇语句是:
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);
}
请说明您的意思“我无法获得价值....”。观察到的行为是什么? – ZbynekZ
我能够获得服务器上的所有节点的所有属性/值和节点“Channel1.Device1.Tag1”我可以获取所有属性/值(如DataType,Address,Description),但我是没有得到持有“Tag1”实际价值的财产 –