OPC Studio User's Guide and Reference
IsNull Property (UANodeId)



OpcLabs.EasyOpcUA Assembly > OpcLabs.EasyOpc.UA.AddressSpace Namespace > UANodeId Class : IsNull Property
Determines whether the node Id is null.
Syntax
'Declaration
 
Public ReadOnly Property IsNull As Boolean
'Usage
 
Dim instance As UANodeId
Dim value As Boolean
 
value = instance.IsNull
public bool IsNull {get;}
public:
property bool IsNull {
   bool get();
}

Property Value

The default value of this property is True.

Remarks

A UANodeId is null when its UANamespaceQualified.NamespaceUriString is empty, and its node Id type is UANodeIdType.None.

Note that the OPC UA node Id, as per OPC specifications, is considered null in a larger number of cases. When UANodeId is constructed from the OPC UA node Id, however, any null node Id is coalesced into Null.

The getter method of this property is pure, i.e. it does not have observable side effects.

This method or property does not throw any exceptions, aside from execution exceptions such as System.Threading.ThreadAbortException or System.OutOfMemoryException.

OPC UA node Id, represented by the UANodeId class, directly identifies a node in a server's address space.

Requirements

Target Platforms: .NET Framework: Windows 10 (selected versions), Windows 11 (selected versions), Windows Server 2016, Windows Server 2022; .NET: Linux, macOS, Microsoft Windows

See Also

Reference

UANodeId Class
UANodeId Members
OPC UA Node IDs
Namespace indices in OPC UA Node Ids