QuickOPC User's Guide and Reference
DAItemDescriptor Constructor(DANodeElement,VarType)



OpcLabs.EasyOpcClassicCore Assembly > OpcLabs.EasyOpc.DataAccess Namespace > DAItemDescriptor Class > DAItemDescriptor Constructor : DAItemDescriptor Constructor(DANodeElement,VarType)
The node element object - contains information gathered about a node in OPC server's address space.
Specifies the data type requested. Passing OpcLabs.BaseLib.ComInterop.VarTypes.Empty means that the server's canonical data type should be used.
Initializes a new instance of the DAItemDescriptor class.Initializes a new instance of the class, from specified node element, and data type.
Syntax
'Declaration
 
Public Function New( _
   ByVal nodeElement As DANodeElement, _
   ByVal requestedDataType As VarType _
)
'Usage
 
Dim nodeElement As DANodeElement
Dim requestedDataType As VarType
 
Dim instance As New DAItemDescriptor(nodeElement, requestedDataType)
public DAItemDescriptor( 
   DANodeElement nodeElement,
   VarType requestedDataType
)
public:
DAItemDescriptor( 
   DANodeElement^ nodeElement,
   VarType^ requestedDataType
)

Parameters

nodeElement
The node element object - contains information gathered about a node in OPC server's address space.
requestedDataType
Specifies the data type requested. Passing OpcLabs.BaseLib.ComInterop.VarTypes.Empty means that the server's canonical data type should be used.
Exceptions
ExceptionDescription

One of the arguments provided to a method is not valid.

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.

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.

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