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12.16 ModelChangeStructureDataType ToC Previous Next index

This structure contains elements that describe changes of the model. Its composition is defined in Table 156.

Table 156 – ModelChangeStructureDataType Structure

Name Type Description
ModelChangeStructure DataType structure  
   affected NodeId NodeId   of the Node that was changed. The client should assume that the affected Node has been created or deleted, had a Reference added or deleted, or the DataType has changed as described by the verb.
   affectedType NodeId If the affected Node was an Object or Variable, affectedType contains the NodeId of the TypeDefinitionNode of the affected Node. Otherwise it is set to null.
   verb Byte Describes the changes happening to the affected Node.
The verb is an 8-bit unsigned integer used as bit mask with the structure defined in the following table:

   Field   Bit   Description
   NodeAdded   0   Indicates the affected Node has been added.
   NodeDeleted   1   Indicates the affected Node has been deleted.
   ReferenceAdded   2   Indicates a Reference has been added. The affected Node may be either a SourceNode or TargetNode. Note that an added bidirectional Reference is reflected by two changes.
   ReferenceDeleted   3   Indicates a Reference has been deleted. The affected Node may be either a SourceNode or TargetNode. Note that a deleted bidirectional Reference is reflected by two changes.
   DataTypeChanged   4   This verb may be used only for affected Nodes that are Variables or VariableTypes. It indicates that the DataType Attribute has changed.
   Reserved   5:7   Reserved for future use. Shall always be zero.

A verb may identify several changes on the affected Node at once. This feature should be used if event compression is used (see OPC 10000-3 for details).
Note that all verbs shall always be considered in the context where the ModelChangeStructureDataType is used. A NodeDeleted may indicate that a Node was removed from a view but still exists in other Views.

Its representation in the AddressSpace is defined in Table 157.

Table 157 – ModelChangeStructureDataType Definition

Attributes Value
BrowseName ModelChangeStructureDataType

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