Examples - OPC Data Access - Read an array value

.NET

C#
VB.NET

// Shows how to read an OPC item that is of array type.
//
// Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .
// OPC client and subscriber examples in C# on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-CSharp .
// Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own
// a commercial license in order to use Online Forums, and we reply to every post.

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

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

            Console.WriteLine("Reading array value...");
            int[] value;
            try
            {
                // UInt16 is returned as Int32, because UInt16 is not a CLS-compliant type (and is not supported in VB.NET).
                value = (int[])client.ReadItemValue("", "OPCLabs.KitServer.2", "Simulation.ReadValue_ArrayOfUI2");
            }
            catch (OpcException opcException)
            {
                Console.WriteLine("*** Failure: {0}", opcException.GetBaseException().Message);
                return;
            }

            if (!(value is null))
            {
                Console.WriteLine(value[0]);
                Console.WriteLine(value[1]);
                Console.WriteLine(value[2]);
            }
        }
    }
}

' Shows how to read an OPC item that is of array type.
'
' Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .
' OPC client and subscriber examples in VB.NET on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-VBNET .
' Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own
' a commercial license in order to use Online Forums, and we reply to every post.

Imports OpcLabs.EasyOpc.DataAccess
Imports OpcLabs.EasyOpc.OperationModel

Namespace DataAccess._EasyDAClient
    Partial Friend Class ReadItemValue
        Public Shared Sub Array()
            Dim client As New EasyDAClient()

            Console.WriteLine("Reading array value...")
            Dim value As Int32()
            Try
                ' UInt16 is returned as Int32, because UInt16 is not a CLS-compliant type (and is not supported in VB.NET).
                value = CType(client.ReadItemValue("", "OPCLabs.KitServer.2", "Simulation.ReadValue_ArrayOfUI2"), Int32())
            Catch opcException As OpcException
                Console.WriteLine("*** Failure: {0}", opcException.GetBaseException().Message)
                Exit Sub
            End Try

            If Not IsNothing(value) Then
                Console.WriteLine(value(0))
                Console.WriteLine(value(1))
                Console.WriteLine(value(2))
            End If
        End Sub
    End Class
End Namespace

Python

Python (.NET)

# Shows how to read an OPC item that is of array type.
#
# Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .
# OPC client and subscriber examples in Python on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-Python .
# Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own
# a commercial license in order to use Online Forums, and we reply to every post.
# The QuickOPC package is needed. Install it using "pip install opclabs_quickopc".
import opclabs_quickopc

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


# Instantiate the client object
client = EasyDAClient()

print('Reading array value...')
try:
    # UInt16 is returned as Int32, because UInt16 is not a CLS-compliant type (and is not supported in VB.NET).
    value = IEasyDAClientExtension.ReadItemValue(client, '', 'OPCLabs.KitServer.2', 'Simulation.ReadValue_ArrayOfUI2')
except OpcException as opcException:
    print('*** Failure: ' + opcException.GetBaseException().Message, sep='')
    exit()

# Display results
if value is not None:
    print(value[0])
    print(value[1])
    print(value[2])