AcknowledgeCondition Method (

Acknowledges a condition in the Event Server. Uses server descriptor for specifying the OPC server. Use default acknowledger ID and an empty comment.

Syntax

Visual Basic
C#
C++/CLI

'Declaration
 
Sub AcknowledgeCondition( _
   ByVal serverDescriptor As Object, _
   ByVal sourceDescriptor As Object, _
   ByVal conditionName As String, _
   ByVal activeTime As Date, _
   ByVal cookie As Integer, _
   ByVal acknowledgerId As String, _
   ByVal comment As String _
)

'Usage
 
Dim instance As _EasyAEClient
Dim serverDescriptor As Object
Dim sourceDescriptor As Object
Dim conditionName As String
Dim activeTime As Date
Dim cookie As Integer
Dim acknowledgerId As String
Dim comment As String
 
instance.AcknowledgeCondition(serverDescriptor, sourceDescriptor, conditionName, activeTime, cookie, acknowledgerId, comment)

void AcknowledgeCondition( 
   object serverDescriptor,
   object sourceDescriptor,
   string conditionName,
   DateTime activeTime,
   int cookie,
   string acknowledgerId,
   string comment
)

void AcknowledgeCondition( 
   Object^ serverDescriptor,
   Object^ sourceDescriptor,
   String^ conditionName,
   DateTime activeTime,
   int cookie,
   String^ acknowledgerId,
   String^ comment
)

Parameters

serverDescriptor: The OPC server involved in the operation.
sourceDescriptor: Contains fully qualified source name. Identifies the source of the condition that is being acknowledged, e.g. FIC101.
conditionName: A condition name, identifying the condition that is being acknowledged. Condition Names are unique within the scope of the event server. Examples of Condition Names might be "LevelAlarm" or "Deviation".
activeTime: An active time corresponding to the Source and Condition Name pair. This parameter uniquely identifies a specific transition of the condition to the active state or into a different sub-condition and is the same as the OpcLabs.EasyOpc.AlarmsAndEvents.AEConditionState.SubconditionActiveTime condition attribute. Active Times are passed to the client in the event notification. If the condition has become active again or transitioned into a different sub-condition at a later time, this acknowledgment will be ignored.
cookie: A server supplied "cookie" corresponding to the Source and Condition Name pair that in addition to the Active Time uniquely identifies a specific event notification. Cookies are passed to the client in the event notification. The client is responsible for returning the same cookie parameter, received in the event notification, back to the server in the condition acknowledgment.
acknowledgerId
comment

Exceptions

Exception Description

Exception	Description
System.ArgumentNullException	A `null` reference (`Nothing` in Visual Basic) is passed to a method that does not accept it as a valid argument. This is a usage error, i.e. it will never occur (the exception will not be thrown) in a correctly written program. Your code should not catch this exception.
System.ArgumentOutOfRangeException	The value of an argument is outside the allowable range of values as defined by the invoked method. This is a usage error, i.e. it will never occur (the exception will not be thrown) in a correctly written program. Your code should not catch this exception.
OpcLabs.EasyOpc.OperationModel.OpcException	The OPC "Classic" (or OPC XML-DA) operation has failed. This operation exception in uniformly used to allow common handling of various kinds of errors. The System.Exception.InnerException always contains information about the actual error cause. This is an operation error that depends on factors external to your program, and thus cannot be always avoided. Your code must handle it appropriately.

System.ArgumentNullException

A null reference (Nothing in Visual Basic) is passed to a method that does not accept it as a valid argument.

This is a usage error, i.e. it will never occur (the exception will not be thrown) in a correctly written program. Your code should not catch this exception.

System.ArgumentOutOfRangeException

The value of an argument is outside the allowable range of values as defined by the invoked method.

This is a usage error, i.e. it will never occur (the exception will not be thrown) in a correctly written program. Your code should not catch this exception.

OpcLabs.EasyOpc.OperationModel.OpcException

The OPC "Classic" (or OPC XML-DA) operation has failed. This operation exception in uniformly used to allow common handling of various kinds of errors. The System.Exception.InnerException always contains information about the actual error cause.

This is an operation error that depends on factors external to your program, and thus cannot be always avoided. Your code must handle it appropriately.

Example

.NET

// This example shows how to acknowledge an event condition in the OPC server.
//
// Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .

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

namespace DocExamples.AlarmsAndEvents._EasyAEClient
{
    class AcknowledgeCondition
    {
        // Instantiate the OPC-A&E client object.
        static readonly EasyAEClient AEClient = new EasyAEClient();

        // Instantiate the OPC-DA client object.
        static readonly EasyDAClient DAClient = new EasyDAClient();

        static volatile bool _done;

        public static void Main1()
        {
            var eventHandler = new EasyAENotificationEventHandler(AEClient_Notification);
            AEClient.Notification += eventHandler;

            Console.WriteLine("Processing event notifications for 1 minute...");
            var subscriptionFilter = new AESubscriptionFilter
            {
                Sources = new AENodeDescriptor[] { "Simulation.ConditionState1" }
            };
            int handle = AEClient.SubscribeEvents("", "OPCLabs.KitEventServer.2", 1000, null, subscriptionFilter);

            // Give the refresh operation time to complete
            Thread.Sleep(5 * 1000);

            // Trigger an acknowledgeable event
            try
            {
                DAClient.WriteItemValue("", "OPCLabs.KitServer.2", "SimulateEvents.ConditionState1.Activate", true);
            }
            catch (OpcException opcException)
            {
                Console.WriteLine("*** Failure: {0}", opcException.GetBaseException().Message);
                return;
            }

            _done = false;
            DateTime endTime = DateTime.Now + new TimeSpan(0, 0, 5);
            while ((!_done) && (DateTime.Now < endTime))
                Thread.Sleep(1000);

            // Give some time to also receive the acknowledgement notification
            Thread.Sleep(5 * 1000);

            AEClient.UnsubscribeEvents(handle);
            AEClient.Notification -= eventHandler;
        }

        // Notification event handler
        static void AEClient_Notification(object sender, EasyAENotificationEventArgs e)
        {
            Console.WriteLine();
            if (!e.Succeeded)
            {
                Console.WriteLine("*** Failure: {0}", e.ErrorMessageBrief);
                return;
            }

            Console.WriteLine("Refresh: {0}", e.Refresh);
            Console.WriteLine("RefreshComplete: {0}", e.RefreshComplete);
            AEEventData eventData = e.EventData;
            if (!(eventData is null))
            {
                Console.WriteLine("Event.QualifiedSourceName: {0}", eventData.QualifiedSourceName);
                Console.WriteLine("Event.Message: {0}", eventData.Message);
                Console.WriteLine("Event.Active: {0}", eventData.Active);
                Console.WriteLine("Event.Acknowledged: {0}", eventData.Acknowledged);
                Console.WriteLine("Event.AcknowledgeRequired: {0}", eventData.AcknowledgeRequired);

                if (eventData.AcknowledgeRequired)
                {
                    Console.WriteLine(">>>>> ACKNOWLEDGING THIS EVENT");
                    try
                    {
                        AEClient.AcknowledgeCondition("", "OPCLabs.KitEventServer.2", "Simulation.ConditionState1", "Simulated",
                            eventData.ActiveTime, eventData.Cookie);
                    }
                    catch (OpcException opcException)
                    {
                        Console.WriteLine("*** Failure: {0}", opcException.GetBaseException().Message);
                        return;
                    }
                    Console.WriteLine(">>>>> EVENT ACKNOWLEDGED");
                    _done = true;
                }
            }
        }
    }
}

# This example shows how to acknowledge an event condition in the OPC server.
#
# 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 .
# The QuickOPC package is needed. Install it using "pip install opclabs_quickopc".
import opclabs_quickopc
import time

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


# Notification event handler
def notification(sender, e):
    global aeClient
    global done

    if not e.Succeeded:
        print('*** Failure: ', e.ErrorMessageBrief, sep='')
        return
    print('Refresh: ', e.Refresh, sep='')
    print('RefreshComplete: ', e.RefreshComplete, sep='')
    eventData = e.EventData
    if eventData is not None:
        print('EventData.QualifiedSourceName: ', eventData.QualifiedSourceName, sep='')
        print('EventData.Message: ', eventData.Message, sep='')
        print('EventData.Active: ', eventData.Active, sep='')
        print('EventData.ActiveTime: ', eventData.ActiveTime, sep='')
        print('EventData.ActiveTimeTicks: ', eventData.ActiveTimeTicks, sep='')
        print('EventData.Acknowledged: ', eventData.Acknowledged, sep='')
        print('EventData.AcknowledgeRequired: ', eventData.AcknowledgeRequired, sep='')
        print('EventData.Cookie: ', eventData.Cookie, sep='')
        if eventData.AcknowledgeRequired:
            print('>>>>> ACKNOWLEDGING THIS EVENT')
            try:
                IEasyAEClientExtension.AcknowledgeCondition(aeClient,
                                                            '', 'OPCLabs.KitEventServer.2',
                                                            'Simulation.ConditionState1', 'Simulated',
                                                            eventData.ActiveTimeTicks, eventData.Cookie,
                                                            'Myself')  # acknowledgerId
                # The precise ActiveTime is important for event acknowledgement in OPC A&E. Python.NET, however,
                # represents .NET DateTime to Python 'datetime' object, possibly losing precision. For this reason,
                # use AEEventData.ActiveTimeTicks (as above), and not AEEventData.ActiveTime.
                # aeClient.AcknowledgeCondition('', 'OPCLabs.KitEventServer.2',
                #                               'Simulation.ConditionState1', 'Simulated',
                #                               eventData.ActiveTime, eventData.Cookie)
            except OpcException as opcException:
                print('*** Failure: ' + opcException.GetBaseException().Message)
                done = True
                return
            print('>>>>> EVENT ACKNOWLEDGED')
            done = True


# Instantiate the OPC-A&E client object.
aeClient = EasyAEClient()

# Instantiate the OPC-DA client object.
daClient = EasyDAClient()

#
aeClient.Notification += notification

print('Processing event notifications for 1 minute...')
subscriptionFilter = AESubscriptionFilter()
subscriptionFilter.Sources = [AENodeDescriptor('Simulation.ConditionState1')]
handle = IEasyAEClientExtension.SubscribeEvents(aeClient, '', 'OPCLabs.KitEventServer.2', 1000, None,
                                                subscriptionFilter)

# Give the refresh operation time to complete.
time.sleep(5)

# Trigger an acknowledgeable event.
done = False
try:
    IEasyDAClientExtension.WriteItemValue(daClient, '', 'OPCLabs.KitServer.2',
                                          'SimulateEvents.ConditionState1.Activate', True)
except OpcException as opcException:
    print('*** Failure: ' + opcException.GetBaseException().Message)
    exit()

endTime = time.time() + 60
while (not done) and (time.time() < endTime):
    time.sleep(1)

# Give some time to also receive the acknowledgement notification.
time.sleep(5)

aeClient.UnsubscribeAllEvents()
aeClient.Notification -= notification

print('Finished.')

' This example shows how to acknowledge an event condition in the OPC server.
'
' Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .

Imports System.Threading
Imports OpcLabs.EasyOpc.AlarmsAndEvents
Imports OpcLabs.EasyOpc.AlarmsAndEvents.OperationModel
Imports OpcLabs.EasyOpc.DataAccess
Imports OpcLabs.EasyOpc.OperationModel

Namespace AlarmsAndEvents._EasyAEClient

    Friend Class AcknowledgeCondition
        _
        Private Shared ReadOnly AEClient As New EasyAEClient()
        _
        Private Shared ReadOnly DAClient As New EasyDAClient()

        Private Shared _done As Boolean ' volatile

        Public Shared Sub Main1()
            Dim eventHandler = New EasyAENotificationEventHandler(AddressOf AEClient_Notification)
            AddHandler AEClient.Notification, eventHandler

            Console.WriteLine("Processing event notifications for 1 minute...")
            Dim subscriptionFilter As New AESubscriptionFilter
            subscriptionFilter.Sources = New AENodeDescriptor() {"Simulation.ConditionState1"}
            Dim handle As Integer = AEClient.SubscribeEvents("", "OPCLabs.KitEventServer.2", 1000, Nothing, subscriptionFilter)

            ' Give the refresh operation time to complete
            Thread.Sleep(5 * 1000)

            ' Trigger an acknowledgeable event
            Try
                DAClient.WriteItemValue("", "OPCLabs.KitServer.2", "SimulateEvents.ConditionState1.Activate", True)
            Catch opcException As OpcException
                Console.WriteLine("*** Failure: {0}", opcException.GetBaseException().Message)
                Exit Sub
            End Try

            _done = False
            Dim endTime As Date = Date.Now + New TimeSpan(0, 0, 5)
            Do While ((Not _done)) AndAlso (Date.Now < endTime)
                Thread.Sleep(1000)
            Loop

            ' Give some time to also receive the acknowledgement notification
            Thread.Sleep(5 * 1000)

            AEClient.UnsubscribeEvents(handle)
            RemoveHandler AEClient.Notification, eventHandler
        End Sub

        ' Notification event handler
        Private Shared Sub AEClient_Notification(ByVal sender As Object, ByVal e As EasyAENotificationEventArgs)
            Console.WriteLine()
            If Not e.Succeeded Then
                Console.WriteLine("*** Failure: {0}", e.ErrorMessageBrief)
                Exit Sub
            End If

            Console.WriteLine("Refresh: {0}", e.Refresh)
            Console.WriteLine("RefreshComplete: {0}", e.RefreshComplete)
            If e.EventData IsNot Nothing Then
                Dim eventData As AEEventData = e.EventData
                Console.WriteLine("EventData.QualifiedSourceName: {0}", eventData.QualifiedSourceName)
                Console.WriteLine("EventData.Message: {0}", eventData.Message)
                Console.WriteLine("EventData.Active: {0}", eventData.Active)
                Console.WriteLine("EventData.Acknowledged: {0}", eventData.Acknowledged)
                Console.WriteLine("EventData.AcknowledgeRequired: {0}", eventData.AcknowledgeRequired)

                If eventData.AcknowledgeRequired Then
                    Console.WriteLine(">>>>> ACKNOWLEDGING THIS EVENT")
                    Try
                        AEClient.AcknowledgeCondition("", "OPCLabs.KitEventServer.2", "Simulation.ConditionState1", "Simulated", eventData.ActiveTime, eventData.Cookie)
                    Catch opcException As OpcException
                        Console.WriteLine("*** Failure: {0}", opcException.GetBaseException().Message)
                        Exit Sub
                    End Try
                    Console.WriteLine(">>>>> EVENT ACKNOWLEDGED")
                    _done = True
                End If
            End If
        End Sub
    End Class
End Namespace

VBScript

Rem This example shows how to acknowledge an event condition in the OPC server.
Rem
Rem Find all latest examples here : https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .

Option Explicit

Dim DAClient: Set DAClient = CreateObject("OpcLabs.EasyOpc.DataAccess.EasyDAClient")
Dim AEClient: Set AEClient = CreateObject("OpcLabs.EasyOpc.AlarmsAndEvents.EasyAEClient")

WScript.Echo "Hooking event handler..."
WScript.ConnectObject AEClient, "AEClient_"

Dim ServerDescriptor: Set ServerDescriptor = CreateObject("OpcLabs.EasyOpc.ServerDescriptor")
ServerDescriptor.ServerClass = "OPCLabs.KitEventServer.2"

Dim SourceDescriptor: Set SourceDescriptor = CreateObject("OpcLabs.EasyOpc.AlarmsAndEvents.AENodeDescriptor")
SourceDescriptor.QualifiedName = "Simulation.ConditionState1"

WScript.Echo "Processing event notifications for 1 minute..."
Dim SubscriptionParameters: Set SubscriptionParameters = CreateObject("OpcLabs.EasyOpc.AlarmsAndEvents.AESubscriptionParameters")
SubscriptionParameters.Filter.Sources = Array(SourceDescriptor)
SubscriptionParameters.NotificationRate = 1000
Dim handle: handle = AEClient.SubscribeEvents(ServerDescriptor, SubscriptionParameters, True, Nothing)

WScript.Echo "Give the refresh operation time to complete: Waiting for 5 seconds..."
WScript.Sleep 5*1000

WScript.Echo "Triggering an acknowledgeable event..."
On Error Resume Next
DAClient.WriteItemValue "", "OPCLabs.KitServer.2", "SimulateEvents.ConditionState1.Activate", True
If Err.Number <> 0 Then
    WScript.Echo "*** Failure: " & Err.Source & ": " & Err.Description
    WScript.Quit
End If
On Error Goto 0

Dim done: done = False
Dim endTime: endTime = Now() + 5*(1/24/60/60)
While (Not done) And (Now() < endTime)
    WScript.Sleep 1000
WEnd

WScript.Echo "Give some time to also receive the acknowledgement notification: Waiting for 5 seconds..."
WScript.Sleep 5*1000

WScript.Echo "Unsubscribing events..."
AEClient.UnsubscribeEvents handle

WScript.Echo "Unhooking event handler..."
WScript.DisconnectObject AEClient

WScript.Echo "Finished."



Rem Notification event handler
Sub AEClient_Notification(Sender, e)
    If Not (e.Succeeded) Then
        WScript.Echo "*** Failure: " & e.ErrorMessageBrief
        Exit Sub
    End If

    WScript.Echo 
    WScript.Echo "Refresh: " & e.Refresh
    WScript.Echo "RefreshComplete: " & e.RefreshComplete
    If Not (e.EventData Is Nothing) Then
        With e.EventData
            WScript.Echo "EventData.QualifiedSourceName: " & .QualifiedSourceName
            WScript.Echo "EventData.Message: " & .Message
            WScript.Echo "EventData.Active: " & .Active
            WScript.Echo "EventData.Acknowledged: " & .Acknowledged
            WScript.Echo "EventData.AcknowledgeRequired: " & .AcknowledgeRequired

            If .AcknowledgeRequired Then
                WScript.Echo ">>>>> ACKNOWLEDGING THIS EVENT"
                On Error Resume Next
                AEClient.AcknowledgeCondition ServerDescriptor, SourceDescriptor, "Simulated", _
                    .ActiveTime, .Cookie, "aUser", ""
                If Err.Number <> 0 Then
                    WScript.Echo "*** Failure: " & Err.Source & ": " & Err.Description
                    Exit Sub
                End If
                On Error Goto 0
                WScript.Echo ">>>>> EVENT ACKNOWLEDGED"
                done = True
            End If
        End With
    End If
End Sub

Requirements

Target Platforms: .NET Framework: Windows 10 (selected versions), Windows 11 (selected versions), Windows Server 2016, Windows Server 2022; .NET: Linux, macOS, Microsoft Windows

Reference

_EasyAEClient Interface
_EasyAEClient Members

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