using OpcLabs.EasyOpc.DataAccess.OperationModel; // ReSharper disable CheckNamespace // ReSharper disable InconsistentNaming #region Example // This example shows how subscribe to changes of multiple items, and unsubscribe from one of them. using JetBrains.Annotations; using OpcLabs.EasyOpc.DataAccess; using System; using System.Threading; namespace DocExamples { namespace _EasyDAClient { class UnsubscribeItem { public static void Main() { using (var easyDAClient = new EasyDAClient()) { easyDAClient.ItemChanged += easyDAClient_ItemChanged; int[] handleArray = easyDAClient.SubscribeMultipleItems( new[] { new DAItemGroupArguments("", "OPCLabs.KitServer.2", "Simulation.Random", 1000, null), new DAItemGroupArguments("", "OPCLabs.KitServer.2", "Trends.Ramp (1 min)", 1000, null), new DAItemGroupArguments("", "OPCLabs.KitServer.2", "Trends.Sine (1 min)", 1000, null), new DAItemGroupArguments("", "OPCLabs.KitServer.2", "Simulation.Register_I4", 1000, null) }); Console.WriteLine("Processing item changed events for 30 seconds..."); Thread.Sleep(30 * 1000); Console.WriteLine("Unsubscribing from the first item..."); easyDAClient.UnsubscribeItem(handleArray[0]); Console.WriteLine(); Console.WriteLine("Processing item changed events for 30 seconds..."); Thread.Sleep(30 * 1000); } } // Item changed event handler static void easyDAClient_ItemChanged([NotNull] object sender, [NotNull] EasyDAItemChangedEventArgs e) { Console.WriteLine("{0}: {1}", e.Arguments.ItemDescriptor.ItemId, e.Vtq); } } } } #endregion // ReSharper restore InconsistentNaming // ReSharper restore CheckNamespace

var itemChangedEventHandler = new EventHandler<EasyDAItemChangedEventArgs>(this.OPCItemChanged);

var itemChangedEventHandler = new EasyDAItemChangedEventHandler(this.OPCItemChanged);

opc.ItemChanged += OPCItemChanged;