当前位置 博文首页 > 紫之荆：OPC UA 统一架构 (二)
重头戏，捞取数据，才是该干的事。想获取数据，先有数据源DataPrivade，DataPrivade的数据集合不能和BaseDataVariableState的集合存储同一地址，或者称为浅副本
需要提出下面类重新设计，按照自己的idea来做
public class ReferenceNodeManager : CustomNodeManager2
private BaseDataVariableState CreateVariable(NodeState parent, string path, string name, NodeId dataType, int valueRank)
{
BaseDataVariableState variable = new BaseDataVariableState(parent);
variable.SymbolicName = name;
variable.ReferenceTypeId = ReferenceTypes.Organizes;
variable.TypeDefinitionId = VariableTypeIds.BaseDataVariableType;
variable.NodeId = new NodeId(path, NamespaceIndex);
variable.BrowseName = new QualifiedName(path, NamespaceIndex);
variable.DisplayName = new LocalizedText("en", name);
variable.WriteMask = AttributeWriteMask.DisplayName | AttributeWriteMask.Description;
variable.UserWriteMask = AttributeWriteMask.DisplayName | AttributeWriteMask.Description;
variable.DataType = dataType;
variable.ValueRank = valueRank;
variable.AccessLevel = AccessLevels.CurrentReadOrWrite;
variable.UserAccessLevel = AccessLevels.CurrentReadOrWrite;
variable.Historizing = false;
variable.Value = GetNewValue(variable);
variable.StatusCode = StatusCodes.Good;
variable.Timestamp = DateTime.UtcNow;
a） BaseDataVariableState 的属性
SymbolicName: A symbolic name for the node that is not expected to be globally unique.(节点的符号名，不应是全局唯一的。)（百度翻译）
NodeId:The identifier for the node.(节点的标识符)
BrowseName:The browse name of the node.(节点的浏览名称)
DisplayName:The display name for the node.(节点的显示名称)
DataType:The data type for the variable value.(变量值的数据类型)
ValueRank:The number of array dimensions permitted for the variable value.(变量值允许的数组维数)
Value:The value of the variable.(变量的值)(变量：或者称为节点)
个人认为上面属性比较重要，加黑字体的是用到的，其他暂时没用到。
b) 数据存储在不同区域，下面定义
可能有的用到，有的没用到
1 #region Read
2 // Real BaseDataVariableState
3 public Dictionary<string, BaseDataVariableState> BaseDataVariableStateDic = new Dictionary<string, BaseDataVariableState>();
4 // temp BaseDataVariableState
5 public Dictionary<string, BaseDataVariableState> BaseDataVariableStateTempDic = new Dictionary<string, BaseDataVariableState>();
6
7 // for example ***_***_*** ,OPC
8 private readonly Dictionary<string, String> baseDataVariableToXXXXDic = new Dictionary<string, String>();
9 // for example ***.***.*** ,IOServer
10 private Dictionary<string, String> XXXXToBaseDataVariableDic = new Dictionary<string, String>();
11 #endregion
12
13 #region Write
14 private List<InterfaceSample.Model.ValueItem> writeDataList = new List<InterfaceSample.Model.ValueItem>();
15 private Dictionary<string, BaseDataVariableState> baseDataVariableDicWrite = new Dictionary<string, BaseDataVariableState>();
16 #endregion
17
18 public InterfaceSample.OPCUADataProvide OpcuaDataPrivade = null;
19
20 private object _obj = new object();
21 #endregion
c） 获取与设置数据Value
1. 定时器更新数据，不要因为数据太多卡住，多次增加线程，争抢资源。放在了CreateAddressSpace里，在OPC UA(一)可以看到。Timer:System.Threading.Timer。
1 m_simulationTimer = new Timer(DoSimulation, cts, 1000, 1000); 2
回调DoSimulation(TimerCallback)，cts(CancellationTokenSource cts)后面解释，DoSimulation里要使用Change，至于为什么需要自己查，不怎么用，用的不好。
1 private void DoSimulation(object state)
2 {
3 try
4 {
5 #region CancellationTokenSource
6 var source = state as CancellationTokenSource;
7
8 if (source == null || cts == null)
9 {
10 return;
11 }
12 if (source.Token.IsCancellationRequested && cts.Token.IsCancellationRequested)
13 {
14 return;
15 }
16 else
17 {
18 if (!cts.Token.IsCancellationRequested)
19 {
20 source = cts;
21 }
22 }
23 #endregion
24
25 if (m_dynamicNodes_temp == null)
26 {
27 return;
28 }
29 m_simulationTimer.Change(0, Timeout.Infinite);
30
31 #region
32 lock (_obj)
33 {
34 string[] strs = new string[baseDataVariableToXXXXDic.Count];
35 baseDataVariableToXXXXDic.Values.CopyTo(strs, 0);
36 List<string> li = new List<string>();
37 foreach (var str in strs)
38 {
39 if (source.Token.IsCancellationRequested)
40 {
41 m_simulationTimer.Change(1000, 1000);
42 return;
43 }
44 li.Add(str);
45 }
46 var obsli = OpcuaDataPrivade.GetItemDatas(li);
47
48 if (obsli == null)
49 {
50 m_simulationTimer.Change(1000, 1000);
51 return;
52 }
53 for (int i = 0; i < obsli.Count; i++)
54 {
55 if (source.Token.IsCancellationRequested)
56 {
57 m_simulationTimer.Change(900, 1000);
58 return;
59 }
60 m_dynamicNodes_temp[i].Value = obsli[i];
61 }
62 }
63
64 #endregion
65
66 lock (Lock)
67 {
68 int count = 0;
69 foreach (BaseDataVariableState variable in m_dynamicNodes_temp)
70 {
71 if (source.Token.IsCancellationRequested)
72 {
73 m_simulationTimer.Change(1000, 1000);
74 return;
75 }
76 77 if (BaseDataVariableStateDic.ContainsKey(variable.NodeId.Identifier.ToString()))
78 {
79 m_dynamicNodes[count].Value = variable.Value;
80 m_dynamicNodes[count].Timestamp = DateTime.UtcNow;
81 m_dynamicNodes[count].ClearChangeMasks(SystemContext, false);
82 ++count;
83
84 }
85 }
86 m_simulationTimer.Change(1000, 1000);
87 //m_simulationTimer = new Timer(DoSimulation, null, 1000, 1000);
88 }
89 }
90 catch (Exception e)
91 {
92 Utils.Trace(e, "Unexpected error doing simulation.");
93 }
94 }
2. 一般地，Client用户端对Value的赋值(输入)在优先级上要高于读取，所以CancellationTokenSource的用处体现在这。
public override void Write( OperationContext context,IList<WriteValue> nodesToWrite,IList<ServiceResult> errors)
不整段代码，贴插入部分，里面有前后，找的话会找到，(override不一定成功，呵)
1 CheckIfSemanticsHaveChanged(systemContext, propertyState, propertyValue, previousPropertyValue);
2 }
3 var baseNode = handle.Node as BaseDataVariableState;
4 if(baseNode != null) nodesToWriteList.Add(baseNode);
5
6 handle.Node.ClearChangeMasks(systemContext, false);
7
8 }
9
10 // check for nothing to do.
11 if (nodesToValidate.Count == 0)
12 {
13 return;
14 }
另外的代码，遥相呼应一下，OPC UA(一) 里的CreateAddressSpace里的Task。
1 public void WriteProcHandle(CancellationTokenSource source)
2 {
3
