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'Declaration
<CLSCompliantAttribute(False)> <ComVisibleAttribute(True)> <GuidAttribute("A506D7B7-0886-4A2F-AD95-7078D666F812")> <InterfaceTypeAttribute(ComInterfaceType.InterfaceIsDual)> Public Interface _EasyDAItemChangedEventArgs
'Usage
Dim instance As _EasyDAItemChangedEventArgs
[CLSCompliant(false)] [ComVisible(true)] [Guid("A506D7B7-0886-4A2F-AD95-7078D666F812")] [InterfaceType(ComInterfaceType.InterfaceIsDual)] public interface _EasyDAItemChangedEventArgs
[CLSCompliant(false)] [ComVisible(true)] [Guid("A506D7B7-0886-4A2F-AD95-7078D666F812")] [InterfaceType(ComInterfaceType.InterfaceIsDual)] public interface class _EasyDAItemChangedEventArgs
// This example subscribes to changes of 2 items separately, and displays rich information available with each item changed // event notification. using System; using System.Diagnostics; using System.Threading; using OpcLabs.EasyOpc.DataAccess; using OpcLabs.EasyOpc.DataAccess.OperationModel; namespace DocExamples.DataAccess._EasyDAItemChangedEventArgs { class General { 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 items..."); client.SubscribeItem("", "OPCLabs.KitServer.2", "Simulation.Random", 5 * 1000); client.SubscribeItem("", "OPCLabs.KitServer.2", "Trends.Ramp (1 min)", 5 * 1000); Console.WriteLine("Processing item changed events for 1 minute..."); Thread.Sleep(60 * 1000); } } static void client_ItemChanged(object sender, EasyDAItemChangedEventArgs e) { Console.WriteLine(); Console.WriteLine($"e.Arguments.State: {e.Arguments.State}"); Console.WriteLine($"e.Arguments.ServerDescriptor.MachineName: {e.Arguments.ServerDescriptor.MachineName}"); Console.WriteLine($"e.Arguments.ServerDescriptor.ServerClass: {e.Arguments.ServerDescriptor.ServerClass}"); Console.WriteLine($"e.Arguments.ItemDescriptor.ItemId: {e.Arguments.ItemDescriptor.ItemId}"); Console.WriteLine($"e.Arguments.ItemDescriptor.AccessPath: {e.Arguments.ItemDescriptor.AccessPath}"); Console.WriteLine($"e.Arguments.ItemDescriptor.RequestedDataType: {e.Arguments.ItemDescriptor.RequestedDataType}"); Console.WriteLine($"e.Arguments.GroupParameters.Locale: {e.Arguments.GroupParameters.Locale}"); Console.WriteLine($"e.Arguments.GroupParameters.RequestedUpdateRate: {e.Arguments.GroupParameters.RequestedUpdateRate}"); Console.WriteLine($"e.Arguments.GroupParameters.PercentDeadband: {e.Arguments.GroupParameters.PercentDeadband}"); if (e.Succeeded) { Debug.Assert(!(e.Vtq is null)); Console.WriteLine($"e.Vtq.Value: {e.Vtq.Value}"); Console.WriteLine($"e.Vtq.Timestamp: {e.Vtq.Timestamp}"); Console.WriteLine($"e.Vtq.TimestampLocal: {e.Vtq.TimestampLocal}"); Console.WriteLine($"e.Vtq.Quality: {e.Vtq.Quality}"); } else { Debug.Assert(!(e.Exception is null)); Console.WriteLine($"e.Exception.Message: {e.Exception.Message}"); Console.WriteLine($"e.Exception.Source: {e.Exception.Source}"); } } // Example output: // //Processing item changed events for 1 minute... // //e.Arguments.State: //e.Arguments.ServerDescriptor.MachineName: //e.Arguments.ServerDescriptor.ServerClass: OPCLabs.KitServer.2 //e.Arguments.ItemDescriptor.ItemId: Simulation.Random //e.Arguments.ItemDescriptor.AccessPath: //e.Arguments.ItemDescriptor.RequestedDataType: Empty //e.Arguments.GroupParameters.Locale: 0 //e.Arguments.GroupParameters.RequestedUpdateRate: 5000 //e.Arguments.GroupParameters.PercentDeadband: 0 //e.Vtq.Value: 0.00125125888851588 //e.Vtq.Timestamp: 4/10/2020 4:35:25 PM //e.Vtq.TimestampLocal: 4/10/2020 6:35:25 PM //e.Vtq.Quality: GoodNonspecific (192) // //e.Arguments.State: //e.Arguments.ServerDescriptor.MachineName: //e.Arguments.ServerDescriptor.ServerClass: OPCLabs.KitServer.2 //e.Arguments.ItemDescriptor.ItemId: Trends.Ramp(1 min) //e.Arguments.ItemDescriptor.AccessPath: //e.Arguments.ItemDescriptor.RequestedDataType: Empty //e.Arguments.GroupParameters.Locale: 0 //e.Arguments.GroupParameters.RequestedUpdateRate: 5000 //e.Arguments.GroupParameters.PercentDeadband: 0 //e.Vtq.Value: 0.431881904602051 //e.Vtq.Timestamp: 4/10/2020 4:35:25 PM //e.Vtq.TimestampLocal: 4/10/2020 6:35:25 PM //e.Vtq.Quality: GoodNonspecific (192) // //... } }
Rem This example subscribes to changes of 2 items separately, and displays rich information available with each item changed Rem event notification. Option Explicit Dim Client: Set Client = CreateObject("OpcLabs.EasyOpc.DataAccess.EasyDAClient") WScript.ConnectObject Client, "Client_" Client.SubscribeItem "", "OPCLabs.KitServer.2", "Simulation.Random", 5*1000 Client.SubscribeItem "", "OPCLabs.KitServer.2", "Trends.Ramp (1 min)", 5*1000 WScript.Echo "Processing item changed events for 1 minute..." WScript.Sleep 60*1000 Sub Client_ItemChanged(Sender, e) On Error Resume Next WScript.Echo WScript.Echo "e.Arguments.State: " & e.Arguments.State WScript.Echo "e.Arguments.ServerDescriptor.MachineName: " & e.Arguments.ServerDescriptor.MachineName WScript.Echo "e.Arguments.ServerDescriptor.ServerClass: " & e.Arguments.ServerDescriptor.ServerClass WScript.Echo "e.Arguments.ItemDescriptor.ItemId: " & e.Arguments.ItemDescriptor.ItemId WScript.Echo "e.Arguments.ItemDescriptor.AccessPath: " & e.Arguments.ItemDescriptor.AccessPath WScript.Echo "e.Arguments.ItemDescriptor.RequestedDataType: " & e.Arguments.ItemDescriptor.RequestedDataType WScript.Echo "e.Arguments.GroupParameters.Locale: " & e.Arguments.GroupParameters.Locale WScript.Echo "e.Arguments.GroupParameters.RequestedUpdateRate: " & e.Arguments.GroupParameters.RequestedUpdateRate WScript.Echo "e.Arguments.GroupParameters.PercentDeadband: " & e.Arguments.GroupParameters.PercentDeadband WScript.Echo "e.Exception.Message: " & e.Exception.Message WScript.Echo "e.Exception.Source: " & e.Exception.Source WScript.Echo "e.Exception.ErrorCode: " & e.Exception.ErrorCode WScript.Echo "e.Vtq.Value: " & e.Vtq.Value WScript.Echo "e.Vtq.Timestamp: " & e.Vtq.Timestamp WScript.Echo "e.Vtq.TimestampLocal: " & e.Vtq.TimestampLocal WScript.Echo "e.Vtq.Quality: " & e.Vtq.Quality End Sub
Target Platforms: .NET Framework: Windows 10 (selected versions), Windows 11 (selected versions), Windows Server 2012, Windows Server 2016; .NET Core, .NET 5, .NET 6: Linux, macOS, Microsoft Windows