OPC Studio User's Guide and Reference
DAHandleGroupArguments Constructor(Int32,DAGroupParameters,Object)



OpcLabs.EasyOpcClassicCore Assembly > OpcLabs.EasyOpc.DataAccess.OperationModel Namespace > DAHandleGroupArguments Class > DAHandleGroupArguments Constructor : DAHandleGroupArguments Constructor(Int32,DAGroupParameters,Object)
A handle value.
An object containing subscription parameters, such as the requested update rate.

Because the OpcLabs.EasyOpc.DataAccess.DAGroupParameters has an implicit conversion from System.Int32, in languages that support implicit conversion operators (such as C# or VB.NET), you can simply use an integer (representing the requested update rate in milliseconds) in place of this parameter, and the corresponding OPC DA group parameters object will be constructed automatically. When the implicit conversion operators are not supported (such as with Python.NET), you can use the DAGroupParameters Constructor(Int32) constructor instead.

The value of this parameter cannot be null (Nothing in Visual Basic).

The state object (can be any value supplied by your code); available in event notifications.

The value of this parameter can be null (Nothing in Visual Basic).

Initializes a new instance of the class, with the specified handle value, OPC group parameters, and a user-defined state object.
Syntax
'Declaration
 
Public Function New( _
   ByVal handle As Integer, _
   ByVal groupParameters As DAGroupParameters, _
   ByVal state As Object _
)
'Usage
 
Dim handle As Integer
Dim groupParameters As DAGroupParameters
Dim state As Object
 
Dim instance As New DAHandleGroupArguments(handle, groupParameters, state)
public DAHandleGroupArguments( 
   int handle,
   DAGroupParameters groupParameters,
   object state
)
public:
DAHandleGroupArguments( 
   int handle,
   DAGroupParameters^ groupParameters,
   Object^ state
)

Parameters

handle
A handle value.
groupParameters
An object containing subscription parameters, such as the requested update rate.

Because the OpcLabs.EasyOpc.DataAccess.DAGroupParameters has an implicit conversion from System.Int32, in languages that support implicit conversion operators (such as C# or VB.NET), you can simply use an integer (representing the requested update rate in milliseconds) in place of this parameter, and the corresponding OPC DA group parameters object will be constructed automatically. When the implicit conversion operators are not supported (such as with Python.NET), you can use the DAGroupParameters Constructor(Int32) constructor instead.

The value of this parameter cannot be null (Nothing in Visual Basic).

state
The state object (can be any value supplied by your code); available in event notifications.

The value of this parameter can be null (Nothing in Visual Basic).

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.

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