The SelectionListType VariableType is used for a Variable where the possible values are provided by a set of values.
The Selections Property contains an array of values which represent valid values for this VariableType’s value. The Selections Property may be dynamic, including changes in the length of the array. The Selections Property may also be empty indicating there are currently no valid values which can be written to the Variable. Clients should either subscribe to the Selections Property or read it just before use.
The DataType of the Selections Property array shall be of the same DataType as this VariableType. When the SelectionListType is subtyped, the DataType of the Selections Property array of the subtype shall be the same DataType as the subtype.When the SelectionListType is instantiated, the DataType of the Selections Property array of the instance shall be the same as the DataType of the instance.
Each array element of the optional SelectionDescriptions Property contains a human-readable representation of the corresponding value in the Selections Property and shall be of the same array size as the Selections Property.
The value of this VariableType may be restricted to only the values defined in the Selections Property by setting the optional RestrictToList Property to a value of True. If the RestrictToList Property is not present or has a value of False then the value is not restricted to the set defined by the Selections Property.
The VariableType is formally defined in Table 86.
Table 86 – SelectionListType definition
|
Attribute |
Value |
||||
|
BrowseName |
SelectionListType |
||||
|
IsAbstract |
False |
||||
|
ValueRank |
-1 (-1 – Scalar) |
||||
|
DataType |
BaseDataType |
||||
|
References |
NodeClass |
Browse Name |
DataType TypeDefinition |
ModellingRule |
|
|
Subtype of the BaseDataVariableType defined in 7.4 |
|||||
|
HasProperty |
Variable |
Selections |
BaseDataType[] PropertyType |
Mandatory |
|
|
HasProperty |
Variable |
SelectionDescriptions |
LocalizedText[] PropertyType |
Optional |
|
|
HasProperty |
Variable |
RestrictToList |
Boolean PropertyType |
Optional |
|
|
Conformance Units |
|||||
|
Base Info Selection List |
|||||