QuickOPC User's Guide and Reference
EasyUADataChangeArguments<TValue> Constructor(EasyUADataChangeNotificationEventHandler<TValue>,Object,UAEndpointDescriptor,UANodeDescriptor)



OpcLabs.EasyOpcUA Assembly > OpcLabs.EasyOpc.UA.Generic Namespace > EasyUADataChangeArguments<TValue> Class > EasyUADataChangeArguments<TValue> Constructor : EasyUADataChangeArguments<TValue> Constructor(EasyUADataChangeNotificationEventHandler<TValue>,Object,UAEndpointDescriptor,UANodeDescriptor)
A callback method to be invoked for each significant monitored item change.
User-defined state object.
Endpoint descriptor. Identifies the OPC-UA server.
Node descriptor. Identifies the node in OPC server's address space.
Syntax
'Declaration
 
Public Function New( _
   ByVal callback As OpcLabs.EasyOpc.UA.Generic.EasyUADataChangeNotificationEventHandler(Of TValue), _
   ByVal state As Object, _
   ByVal endpointDescriptor As UAEndpointDescriptor, _
   ByVal nodeDescriptor As UANodeDescriptor _
)
'Usage
 
Dim callback As OpcLabs.EasyOpc.UA.Generic.EasyUADataChangeNotificationEventHandler(Of TValue)
Dim state As Object
Dim endpointDescriptor As UAEndpointDescriptor
Dim nodeDescriptor As UANodeDescriptor
 
Dim instance As New EasyUADataChangeArguments(Of TValue)(callback, state, endpointDescriptor, nodeDescriptor)
public EasyUADataChangeArguments<TValue>( 
   OpcLabs.EasyOpc.UA.Generic.EasyUADataChangeNotificationEventHandler<TValue> callback,
   object state,
   UAEndpointDescriptor endpointDescriptor,
   UANodeDescriptor nodeDescriptor
)
public:
EasyUADataChangeArguments<TValue>( 
   OpcLabs.EasyOpc.UA.Generic.EasyUADataChangeNotificationEventHandler<TValue^>^ callback,
   Object^ state,
   UAEndpointDescriptor^ endpointDescriptor,
   UANodeDescriptor^ nodeDescriptor
)

Parameters

callback
A callback method to be invoked for each significant monitored item change.
state
User-defined state object.
endpointDescriptor
Endpoint descriptor. Identifies the OPC-UA server.
nodeDescriptor
Node descriptor. Identifies the node in OPC server's address space.
Remarks

If callback is a null reference, only the OpcLabs.EasyOpc.UA.EasyUAClientCore.DataChangeNotification event is generated, and no callback method is invoked.

You can obtain nodeDescriptor e.g. by calling one of the browsing methods on OpcLabs.EasyOpc.UA.EasyUAClientCore object.

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