QuickOPC User's Guide and Reference
ReadNodeClass(IEasyUAClient,UANodeArguments) Method



OpcLabs.EasyOpcUA Assembly > OpcLabs.EasyOpc.UA.Extensions Namespace > IEasyUAClientExtension2 Class > ReadNodeClass Method : ReadNodeClass(IEasyUAClient,UANodeArguments) Method
The client object that will perform the operation.
An arguments object that specifies the node in the OPC server.
Reads a value of NodeClass attribute of a node. Reads a value of NodeClass attribute of a node, using an arguments object that holds the node information.
Syntax
'Declaration
 
<ExtensionAttribute()>
Public Overloads Shared Function ReadNodeClass( _
   ByVal client As IEasyUAClient, _
   ByVal nodeArguments As UANodeArguments _
) As UANodeClass
'Usage
 
Dim client As IEasyUAClient
Dim nodeArguments As UANodeArguments
Dim value As UANodeClass
 
value = IEasyUAClientExtension2.ReadNodeClass(client, nodeArguments)

Parameters

client
The client object that will perform the operation.
nodeArguments
An arguments object that specifies the node in the OPC server.

Return Value

If successful, the method returns the actual value of OPC attribute requested.
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

This method also checks whether the returned value is not a reference, and is indeed of the OpcLabs.EasyOpc.UA.AddressSpace.UANodeClass type. The returned value is therefore always a valid OpcLabs.EasyOpc.UA.AddressSpace.UANodeClass.

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