// Hooking up events and receiving OPC item changes.
using System;
using System.Threading;
using OpcLabs.EasyOpc.DataAccess;
using OpcLabs.EasyOpc.DataAccess.OperationModel;
namespace DocExamples.DataAccess._EasyDAClient
{
    partial class SubscribeItem
    {
        public static void Main1()
        {
            // Instantiate the client object.
            using (var client = new EasyDAClient())
            {
                var eventHandler = new EasyDAItemChangedEventHandler(client_ItemChanged);
                client.ItemChanged += eventHandler;
                Console.WriteLine("Subscribing item...");
                client.SubscribeItem("", "OPCLabs.KitServer.2", "Demo.Ramp", 200);
                Console.WriteLine("Process item change notifications for 30 seconds...");
                Thread.Sleep(30 * 1000);
                Console.WriteLine("Unsubscribing all items...");
                client.UnsubscribeAllItems();
                client.ItemChanged -= eventHandler;
            }
            Console.WriteLine("Finished.");
        }
        static void client_ItemChanged(object sender, EasyDAItemChangedEventArgs e)
        {
            if (e.Succeeded)
                Console.WriteLine(e.Vtq);
            else
                Console.WriteLine($"*** Failure: {e.ErrorMessageBrief}");
        }
    }
}
	 
	
		# Hooking up events and receiving OPC item changes.
#requires -Version 5.1
using namespace OpcLabs.EasyOpc.DataAccess
# The path below assumes that the current directory is [ProductDir]/Examples-NET/PowerShell/Windows .
Add-Type -Path "../../../Components/Opclabs.QuickOpc/net472/OpcLabs.EasyOpcClassicCore.dll"
Add-Type -Path "../../../Components/Opclabs.QuickOpc/net472/OpcLabs.EasyOpcClassic.dll"
Add-Type -Path "../../../Components/Opclabs.QuickOpc/net472/OpcLabs.EasyOpcClassicComponents.dll"
# Instantiate the client object.
$client = New-Object EasyDAClient
# Item changed event handler
Register-ObjectEvent -InputObject $client -EventName ItemChanged -Action { 
    if ($EventArgs.Succeeded) {
        Write-Host $EventArgs.Vtq
    }
    else {
        Write-Host "*** Failure: $($EventArgs.ErrorMessageBrief)"
    }
}
Write-Host "Subscribing item..."
[IEasyDAClientExtension]::SubscribeItem($client, "", "OPCLabs.KitServer.2", "Demo.Ramp", 200)
Write-Host "Processing item changes for 30 seconds..."
$stopwatch =  [System.Diagnostics.Stopwatch]::StartNew() 
while ($stopwatch.Elapsed.TotalSeconds -lt 30) {    
    Start-Sleep -Seconds 1
}
Write-Host "Unsubscribing items..."
$client.UnsubscribeAllItems()
Write-Host "Finished."
	 
	
		# Hooking up events and receiving OPC item changes.
# The QuickOPC package is needed. Install it using "pip install opclabs_quickopc".
import opclabs_quickopc
import time
# Import .NET namespaces.
from OpcLabs.EasyOpc.DataAccess import *
# Item changed event handler.
def itemChanged(sender, e):
    if e.Succeeded:
        print(e.Vtq)
    else:
        print('*** Failure: ', e.ErrorMessageBrief, sep='')
# Instantiate the client object.
client = EasyDAClient()
client.ItemChanged += itemChanged
print('Subscribing item changes...')
IEasyDAClientExtension.SubscribeItem(client, '', 'OPCLabs.KitServer.2', 'Demo.Ramp', 200)
print('Processing item change notifications for 30 seconds...')
time.sleep(30)
print('Unsubscribing all items...')
client.UnsubscribeAllItems()
client.ItemChanged -= itemChanged
print('Finished.')
	 
	
		' Hooking up events and receiving OPC item changes.
Imports System.Threading
Imports OpcLabs.EasyOpc.DataAccess
Imports OpcLabs.EasyOpc.DataAccess.OperationModel
Namespace DataAccess._EasyDAClient
    Partial Friend Class SubscribeItem
        Shared Sub Main1()
            Using client = New EasyDAClient()
                Dim eventHandler = New EasyDAItemChangedEventHandler(AddressOf client_ItemChanged)
                AddHandler client.ItemChanged, eventHandler
                Console.WriteLine("Subscribing item...")
                client.SubscribeItem("", "OPCLabs.KitServer.2", "Demo.Ramp", 200)
                Thread.Sleep(30 * 1000)
                client.UnsubscribeAllItems()
                RemoveHandler client.ItemChanged, eventHandler
            End Using
        End Sub
        Private Shared Sub client_ItemChanged(sender As Object, e As EasyDAItemChangedEventArgs)
            If e.Succeeded Then
                Console.WriteLine(e.Vtq)
            Else
                Console.WriteLine("*** Failure: {0}", e.ErrorMessageBrief)
            End If
        End Sub
    End Class
End Namespace