OPC Studio User's Guide and Reference
Enable Method (_EasyUAAlarmsAndConditionsClient)



OpcLabs.EasyOpcUA Assembly > OpcLabs.EasyOpc.UA.AlarmsAndConditions.ComTypes Namespace > _EasyUAAlarmsAndConditionsClient Interface : Enable Method
Endpoint descriptor. Identifies the OPC-UA server.
Node descriptor. Identifies the node in OPC server's address space.
The Enable Method is used to change a Condition instance to the enabled state.
Syntax
'Declaration
 
Sub Enable( _
   ByVal endpointDescriptor As Object, _
   ByVal objectOrConditionNodeDescriptor As Object _
) 
'Usage
 
Dim instance As _EasyUAAlarmsAndConditionsClient
Dim endpointDescriptor As Object
Dim objectOrConditionNodeDescriptor As Object
 
instance.Enable(endpointDescriptor, objectOrConditionNodeDescriptor)

Parameters

endpointDescriptor
Endpoint descriptor. Identifies the OPC-UA server.
objectOrConditionNodeDescriptor
Node descriptor. Identifies the node in OPC server's address space.
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.

The OPC UA operation has failed. This operation exception in uniformly used to allow common handling of various kinds of errors. The System.Exception.InnerException always contains information about the actual error cause.

This is an operation error that depends on factors external to your program, and thus cannot be always avoided. Your code must handle it appropriately.

Remarks
Normally, the NodeId of the object instance as the ObjectId is passed to the Call Service. However, some Servers do not expose Condition instances in the AddressSpace. Therefore, all Servers shall also allow Clients to call the AddComments Method by specifying ConditionId as the ObjectId. The Method cannot be called with an ObjectId of the ConditionType Node. If the Condition instance is not exposed, then it may be difficult for a Client to determine the ConditionId for a disabled Condition.
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