The OrderedListTypeis a base type to manage an ordered list of Objects. It is formally defined in Table 64.

Table 64– OrderedListType Definition

Attribute	Value
BrowseName	OrderedListType
IsAbstract	False
References	Node Class	BrowseName	DataType	TypeDefinition	Other
Subtype of the BaseObjectTypedefined in 6.2i.e. inheriting the InstanceDeclarations of that Node.
HasOrderedComponent	Object	<OrderedObject>		BaseObjectType	OP
HasProperty	Variable	NodeVersion	String	PropertyType	O
GeneratesEvent	ObjectType	GeneralModelChangeEventType
Conformance Units
Base Info OrderedList

The <OrderedObject> Objectrepresents the ordered Objectsmanaged by Instances of the OrderedListType. The order is provided by the 0:HasOrderedComponent Referencesto the Objects. As not all Clientsconsider the order returned by the Browse Service(e.g. displaying the results in alphabetic order) each <OrderedObject>shall implement the IOrderedObjectType Interface, providing the order by a specific Property(see definition of IOrderedObjectType).

The NodeVersionis intended to be used in conjunction with the GeneralModelChangeEventTypein the way defined in OPC 10000-3. The NodeVersion should be provided if the ordered List can change (e.g. new Objectsadded or removed). This allows Clientsto subscribe to the Propertyor the GeneralModelChangeEvents, instead of polling Browse calls. Changes in the order of the List are considered as adding and deleting References, i.e. if the order changes the NodeVersionshall be changed and a GeneralModelChangeEventshall be issued, indicating that Referenceshave been added and deleted.

In Table 65the additional Referencesare defined.

Table 65– OrderedListType Additional Subcomponents

SourcePath	References	NodeClass	BrowseName	DataType	TypeDefinition	Other
<OrderedObject>	HasProperty	Variable	NumberInList	Number	PropertyType	M
<OrderedObject>	HasInterface	ObjectType	IOrderedObjectType

The <OrderedObject> Objectshall implement the Interface IOrderedObjectTypeand therefore contains the mandatory Property NumberInList.