QuickOPC User's Guide and Reference
Examples - OPC Data Access - Write a single value, specify requested data type
// This example shows how to write a value into a single item, specifying its requested data type.

using System;
using OpcLabs.BaseLib.ComInterop;
using OpcLabs.EasyOpc.DataAccess;
using OpcLabs.EasyOpc.OperationModel;

namespace DocExamples.DataAccess._EasyDAClient
{
    partial class WriteItemValue
    {
        public static void RequestedDataType()
        {
            // Instantiate the client object.
            var client = new EasyDAClient();

            try
            {
                client.WriteItemValue("", "OPCLabs.KitServer.2", "Simulation.Register_I4", 12345,
                    VarTypes.I4);   // <-- the requested data type
            }
            catch (OpcException opcException)
            {
                Console.WriteLine("*** Failure: {0}", opcException.GetBaseException().Message);
            }
        }
    }
}
# This example shows how to write a value into a single item, specifying its requested data type.

# The QuickOPC package is needed. Install it using "pip install opclabs_quickopc".
import opclabs_quickopc

# Import .NET namespaces.
from OpcLabs.BaseLib.ComInterop import *
from OpcLabs.EasyOpc.DataAccess import *
from OpcLabs.EasyOpc.OperationModel import *


# Instantiate the client object.
client = EasyDAClient()

# Perform the operation
try:
    IEasyDAClientExtension.WriteItemValue(client, '', 'OPCLabs.KitServer.2', 'Simulation.Register_I4', 12345,
                                          VarType(VarTypes.I4)) # <-- the requested data type
except OpcException as opcException:
    print('*** Failure: ' + opcException.GetBaseException().Message)
    exit()

print('Finished.')
' This example shows how to write a value into a single item, specifying its requested data type.

Imports OpcLabs.BaseLib.ComInterop
Imports OpcLabs.EasyOpc.DataAccess
Imports OpcLabs.EasyOpc.OperationModel

Namespace DataAccess._EasyDAClient
    Partial Friend Class WriteItemValue
        Public Shared Sub RequestedDataType()
            Dim client = New EasyDAClient()

            Try
                client.WriteItemValue("", "OPCLabs.KitServer.2", "Simulation.Register_I4", 12345,
                                      VarTypes.I4) ' <-- the requested data type
            Catch opcException As OpcException
                Console.WriteLine("*** Failure: {0}", opcException.GetBaseException().Message)
                Exit Sub
            End Try
        End Sub
    End Class
End Namespace

 

See Also

Conceptual