/// <summary>
/// Follows hierarchial references from the current node and updates the tree.
/// </summary>
private void Browse(TreeNode parent)
{
parent.Nodes.Clear();
ReferenceDescription start = parent.Tag as ReferenceDescription;
ListOfBrowseDescription nodesToBrowse = new ListOfBrowseDescription();
BrowseDescription nodeToBrowse = new BrowseDescription();
nodeToBrowse.NodeId = new NodeId(start.NodeId);
nodeToBrowse.BrowseDirection = BrowseDirection.Forward_0;
nodeToBrowse.ReferenceTypeId = new NodeId(ReferenceTypes.HierarchicalReferences);
nodeToBrowse.IncludeSubtypes = true;
nodeToBrowse.ResultMask = (uint)DataTypes.EnumToMask(BrowseResultMask.All_63);
nodeToBrowse.NodeClassMask = 0;
nodesToBrowse.Add(nodeToBrowse);
ListOfBrowseResult results;
ListOfDiagnosticInfo diagnosticInfos;
m_client.Browse(
m_client.CreateRequestHeader(),
null,
0,
nodesToBrowse,
out results,
out diagnosticInfos);
if (results != null && results.Count > 0)
{
BrowseResult result = results[0];
if (result.References != null)
{
foreach (ReferenceDescription reference in result.References)
{
TreeNode child = new TreeNode(reference.DisplayName.Text);
child.Tag = reference;
child.Nodes.Add(new TreeNode());
parent.Nodes.Add(child);
}
}
}
}
/// <summary>
/// Returns the value of an attribute.
/// </summary>
public void Read(
ReadValueId request,
DataValue result,
DiagnosticInfo diagnosticInfo)
{
lock (m_lock)
{
// find the node to read.
Node source = m_nodes.Find(request.NodeId);
result.ServerTimestamp = DateTime.UtcNow;
if (source == null)
{
result.StatusCode = new StatusCode(StatusCodes.BadNodeIdUnknown);
return;
}
result.Value = Variant.Null;
// switch on the attribute value.
switch (request.AttributeId)
{
case Attributes.NodeId:
{
result.Value = new Variant(source.NodeId);
break;
}
case Attributes.NodeClass:
{
result.Value = new Variant(DataTypes.EnumToMask(source.NodeClass));
break;
}
case Attributes.BrowseName:
{
result.Value = new Variant(source.BrowseName);
break;
}
case Attributes.DisplayName:
{
result.Value = new Variant(source.DisplayName);
break;
}
case Attributes.Description:
{
result.Value = new Variant(source.Description);
break;
}
case Attributes.WriteMask:
{
result.Value = new Variant(source.WriteMask);
break;
}
case Attributes.UserWriteMask:
{
result.Value = new Variant(source.UserWriteMask);
break;
}
case Attributes.Value:
{
// check if another component has installed a read callback.
ReadValueEventHandler callback = null;
if (m_callbacks.TryGetValue(source.NodeId.Identifier, out callback))
{
result.Value = new Variant(callback());
break;
}
// use the value cached in the node otherwise.
VariableNode variable = source as VariableNode;
if (variable != null)
{
result.Value = variable.Value;
result.SourceTimestamp = DateTime.UtcNow; // The Value attribute requires a SourceTimestamp.
break;
}
VariableTypeNode variableType = source as VariableTypeNode;
if (variableType != null)
{
result.Value = variableType.Value;
result.SourceTimestamp = DateTime.UtcNow; // The Value attribute requires a SourceTimestamp.
break;
}
result.StatusCode = new StatusCode(StatusCodes.BadAttributeIdInvalid);
break;
}
case Attributes.DataType:
{
VariableNode variable = source as VariableNode;
if (variable != null)
{
result.Value = new Variant(variable.DataType);
break;
}
VariableTypeNode variableType = source as VariableTypeNode;
if (variableType != null)
{
result.Value = new Variant(variableType.DataType);
break;
}
result.StatusCode = new StatusCode(StatusCodes.BadAttributeIdInvalid);
break;
}
case Attributes.ValueRank:
{
VariableNode variable = source as VariableNode;
if (variable != null)
{
result.Value = new Variant(variable.ValueRank);
break;
}
VariableTypeNode variableType = source as VariableTypeNode;
if (variableType != null)
{
result.Value = new Variant(variableType.ValueRank);
break;
}
result.StatusCode = new StatusCode(StatusCodes.BadAttributeIdInvalid);
break;
}
case Attributes.MinimumSamplingInterval:
{
VariableNode variable = source as VariableNode;
if (variable != null)
{
result.Value = new Variant(variable.MinimumSamplingInterval);
break;
}
result.StatusCode = new StatusCode(StatusCodes.BadAttributeIdInvalid);
break;
}
case Attributes.Historizing:
{
VariableNode variable = source as VariableNode;
if (variable != null)
{
result.Value = new Variant(variable.Historizing);
break;
}
result.StatusCode = new StatusCode(StatusCodes.BadAttributeIdInvalid);
break;
}
case Attributes.AccessLevel:
{
VariableNode variable = source as VariableNode;
if (variable != null)
{
result.Value = new Variant(variable.AccessLevel);
break;
}
result.StatusCode = new StatusCode(StatusCodes.BadAttributeIdInvalid);
break;
}
case Attributes.UserAccessLevel:
{
VariableNode variable = source as VariableNode;
if (variable != null)
{
result.Value = new Variant(variable.UserAccessLevel);
break;
}
result.StatusCode = new StatusCode(StatusCodes.BadAttributeIdInvalid);
break;
}
case Attributes.EventNotifier:
{
ObjectNode objectn = source as ObjectNode;
if (objectn != null)
{
result.Value = new Variant(objectn.EventNotifier);
break;
}
ViewNode view = source as ViewNode;
if (view != null)
{
result.Value = new Variant(view.EventNotifier);
break;
}
result.StatusCode = new StatusCode(StatusCodes.BadAttributeIdInvalid);
break;
}
case Attributes.Executable:
{
MethodNode method = source as MethodNode;
if (method != null)
{
result.Value = new Variant(method.Executable);
break;
}
result.StatusCode = new StatusCode(StatusCodes.BadAttributeIdInvalid);
break;
}
case Attributes.UserExecutable:
{
MethodNode method = source as MethodNode;
if (method != null)
{
result.Value = new Variant(method.UserExecutable);
break;
}
result.StatusCode = new StatusCode(StatusCodes.BadAttributeIdInvalid);
break;
}
case Attributes.ContainsNoLoops:
{
ViewNode view = source as ViewNode;
if (view != null)
{
result.Value = new Variant(view.ContainsNoLoops);
break;
}
result.StatusCode = new StatusCode(StatusCodes.BadAttributeIdInvalid);
break;
}
case Attributes.InverseName:
{
ReferenceTypeNode referenceType = source as ReferenceTypeNode;
if (referenceType != null)
{
result.Value = new Variant(referenceType.InverseName);
break;
}
result.StatusCode = new StatusCode(StatusCodes.BadAttributeIdInvalid);
break;
}
case Attributes.IsAbstract:
{
DataTypeNode dataType = source as DataTypeNode;
if (dataType != null)
{
result.Value = new Variant(dataType.IsAbstract);
break;
}
ReferenceTypeNode referenceType = source as ReferenceTypeNode;
if (referenceType != null)
{
result.Value = new Variant(referenceType.IsAbstract);
break;
}
ObjectTypeNode objectType = source as ObjectTypeNode;
if (objectType != null)
{
result.Value = new Variant(objectType.IsAbstract);
break;
}
VariableTypeNode variableType = source as VariableTypeNode;
if (variableType != null)
{
result.Value = new Variant(variableType.IsAbstract);
break;
}
result.StatusCode = new StatusCode(StatusCodes.BadAttributeIdInvalid);
break;
}
case Attributes.Symmetric:
{
ReferenceTypeNode referenceType = source as ReferenceTypeNode;
if (referenceType != null)
{
result.Value = new Variant(referenceType.Symmetric);
break;
}
result.StatusCode = new StatusCode(StatusCodes.BadAttributeIdInvalid);
break;
}
default:
{
result.StatusCode = new StatusCode(StatusCodes.BadAttributeIdInvalid);
break;
}
}
}
}