OPC Studio User's Guide and Reference
Isolated Property (EasyDAClientCore)
Example 



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OpcLabs.EasyOpcClassic Assembly > OpcLabs.EasyOpc.DataAccess Namespace > EasyDAClientCore Class : Isolated Property
Specifies that you wish that the EasyDAClientCore object instance works with an "isolated" connection to the OPC server, i.e. one that is not shared with other instances.
Syntax
'Declaration
 
Public Property Isolated As Boolean
 
'Usage
 
Dim instance As EasyDAClientCore
Dim value As Boolean
 
instance.Isolated = value
 
value = instance.Isolated
Remarks

This method or property does not throw any exceptions, aside from execution exceptions such as System.Threading.ThreadAbortException or System.OutOfMemoryException.

Example

.NET

// This example shows how to create and use two isolated client objects, resulting in two separate connections to the target
// OPC DA server.
//
// Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .

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

namespace DocExamples.DataAccess._EasyDAClient
{
    class Isolated
    {
        public static void Main1()
        {
            // Instantiate the client objects and make them isolated
            var client1 = new EasyDAClient { Isolated = true };
            var client2 = new EasyDAClient { Isolated = true };

            // The callback is a local method the displays the value
            void ItemChangedCallback(object sender, EasyDAItemChangedEventArgs eventArgs)
            {
                Debug.Assert(!(eventArgs is null));

                string displayPrefix = $"[{eventArgs.Arguments.State}]";
                if (eventArgs.Succeeded)
                {
                    Debug.Assert(!(eventArgs.Vtq is null));
                    Console.WriteLine($"{displayPrefix} {eventArgs.Vtq}");
                }
                else
                    Console.WriteLine($"{displayPrefix} *** Failure: {eventArgs.ErrorMessageBrief}");
            }

            Console.WriteLine("Subscribing...");
            client1.SubscribeItem("", "OPCLabs.KitServer.2", "Simulation.Random", 1000, ItemChangedCallback, state: 1);
            client2.SubscribeItem("", "OPCLabs.KitServer.2", "Simulation.Random", 1000, ItemChangedCallback, state: 2);

            Console.WriteLine("Processing item changed events for 10 seconds...");
            Thread.Sleep(10 * 1000);

            Console.WriteLine("Unsubscribing...");
            client1.UnsubscribeAllItems();
            client2.UnsubscribeAllItems();

            Console.WriteLine("Waiting for 2 seconds...");
            Thread.Sleep(2 * 1000);
        }
    }
}
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