OPC Studio User's Guide and Reference
Callback Property (EasyDAItemSubscriptionArguments)



OpcLabs.EasyOpcClassicCore Assembly > OpcLabs.EasyOpc.DataAccess.OperationModel Namespace > EasyDAItemSubscriptionArguments Class : Callback Property
A callback method to be invoked for each significant monitored item change.
Syntax
'Declaration
 
<CanBeNullAttribute()>
<XmlIgnoreAttribute()>
Public Property Callback As EasyDAItemChangedEventHandler
'Usage
 
Dim instance As EasyDAItemSubscriptionArguments
Dim value As EasyDAItemChangedEventHandler
 
instance.Callback = value
 
value = instance.Callback
[CanBeNull()]
[XmlIgnore()]
public EasyDAItemChangedEventHandler Callback {get; set;}
[CanBeNull()]
[XmlIgnore()]
public:
property EasyDAItemChangedEventHandler^ Callback {
   EasyDAItemChangedEventHandler^ get();
   void set (    EasyDAItemChangedEventHandler^ value);
}

Property Value

If this is a null reference, only the notification events are generated, but no callback method is invoked.

This value of this property can be null (Nothing in Visual Basic).

The default value of this property is null.

Remarks

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

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