QuickOPC User's Guide and Reference
EasyUAMonitoredItemArguments Constructor(EasyUAEventNotificationEventHandler,Object,UAEndpointDescriptor,UANodeDescriptor,UAMonitoringParameters)



OpcLabs.EasyOpcUA Assembly > OpcLabs.EasyOpc.UA.OperationModel Namespace > EasyUAMonitoredItemArguments Class > EasyUAMonitoredItemArguments Constructor : EasyUAMonitoredItemArguments Constructor(EasyUAEventNotificationEventHandler,Object,UAEndpointDescriptor,UANodeDescriptor,UAMonitoringParameters)
A callback method to be invoked for each event notification.
User-defined state object.
Endpoint descriptor. Identifies the OPC-UA server.
Node descriptor. Identifies the node in OPC server's address space.
Contains monitoring parameters (such as the sampling interval, and the event filter).
Initializes a new instance of the class.
Syntax
'Usage
 
Dim eventCallback As EasyUAEventNotificationEventHandler
Dim state As Object
Dim endpointDescriptor As UAEndpointDescriptor
Dim nodeDescriptor As UANodeDescriptor
Dim monitoringParameters As UAMonitoringParameters
 
Dim instance As New EasyUAMonitoredItemArguments(eventCallback, state, endpointDescriptor, nodeDescriptor, monitoringParameters)

Parameters

eventCallback
A callback method to be invoked for each event notification.
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.
monitoringParameters
Contains monitoring parameters (such as the sampling interval, and the event filter).
Exceptions
ExceptionDescription

A null reference (Nothing in Visual Basic) is passed to a method that does not accept it as a valid argument.

This is a usage error, i.e. it will never occur (the exception will not be thrown) in a correctly written program. Your code should not catch this exception.

Remarks

If eventCallback is a null reference, only the OpcLabs.EasyOpc.UA.EasyUAClientCore.EventNotification 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