'Declaration
 
Protected Overloads Overridable Function OnDataSubscriptionChanged( _
   ByVal serverOperationContext As UAServerOperationContext, _
   ByVal dataSubscription As IUADataSubscription, _
   ByVal action As UADataSubscriptionChangedAction _
) As Boolean

'Usage
 
Dim instance As UADataVariable
Dim serverOperationContext As UAServerOperationContext
Dim dataSubscription As IUADataSubscription
Dim action As UADataSubscriptionChangedAction
Dim value As Boolean
 
value = instance.OnDataSubscriptionChanged(serverOperationContext, dataSubscription, action)

protected virtual bool OnDataSubscriptionChanged( 
   UAServerOperationContext serverOperationContext,
   IUADataSubscription dataSubscription,
   UADataSubscriptionChangedAction action
)

protected:
virtual bool OnDataSubscriptionChanged( 
   UAServerOperationContext^ serverOperationContext,
   IUADataSubscription^ dataSubscription,
   UADataSubscriptionChangedAction action
) 

Parameters

serverOperationContext

The context for the server operation.

The value of this parameter cannot be null (Nothing in Visual Basic).

dataSubscription

The data subscription that is the subject of the change.

The value of this parameter cannot be null (Nothing in Visual Basic).

action

Describes how the data subscription has changed (add/remove/modify).

This method provides a hook for derived classes to react to changes in data subscriptions, allowing for custom logic to be executed when the data subscriptions to this variable's data change.

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