DAItemDescriptor Constructor(String,VarType)

Initializes a new instance of the DAItemDescriptor class.Initializes a new instance of the class, with specified item identifier and data type.

Syntax

Visual Basic
C#
C++/CLI

'Declaration
 
Public Function New( _
   ByVal itemId As String, _
   ByVal requestedDataType As VarType _
)

'Usage
 
Dim itemId As String
Dim requestedDataType As VarType
 
Dim instance As New DAItemDescriptor(itemId, requestedDataType)

public DAItemDescriptor( 
   string itemId,
   VarType requestedDataType
)

public:
DAItemDescriptor( 
   String^ itemId,
   VarType^ requestedDataType
)

Parameters

itemId: Contains OPC item identifier.
requestedDataType: Specifies the data type requested. Passing OpcLabs.BaseLib.ComInterop.VarTypes.Empty means that the server's canonical data type should be used.

Exceptions

Exception Description

Exception	Description
System.ArgumentException	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.
System.ArgumentNullException	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.

System.ArgumentException

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.

System.ArgumentNullException

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

Reference

DAItemDescriptor Class
DAItemDescriptor Members
Overload List

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