property Node.ID as Variant
Retrieves the node's unique identifier.

TypeDescription
Variant A String expression that determines the unique node identifier. 
By default, the ID property is generated by the control, to identify uniquely a node within the Nodes collection. The ItemByID property gets the node giving its identifier. For instance, the ID property looks as: "0.1.1". The RemoveByID method removes a node giving its unique identifier.