The union data type represents a (tagged) union.
In data type dictionary model (the only model before OPC UA 1.04), union data is not directly available. A union can, however, be quite efficiently modeled using an appropriately formed structure with optional fields.
The DataFields Property contains a collection of data fields of the union data type. Each such data field is an instance of DataField Class, and specifies:
- A DataType of the contents of the field.
- A Name: Data field name, unique within the union data type.
- A Description: Human readable description of the data field.
See Also