Connectivity Software User's Guide and Reference
EasyUAEventNotificationEventHandler Delegate
ExampleExample 



OpcLabs.EasyOpcUAPrimitives Assembly > OpcLabs.EasyOpc.UA Namespace : EasyUAEventNotificationEventHandler Delegate
The source of the event.
An OpcLabs.EasyOpc.UA.OperationModel.EasyUAEventNotificationEventArgs that contains the event data.
Represents the method that will handle an event raised for every event notification generated by a subscribed OPC monitored item.
Syntax
'Declaration
 
<ComVisibleAttribute(False)>
Public Delegate Sub EasyUAEventNotificationEventHandler( _
   ByVal sender As Object, _
   ByVal e As EasyUAEventNotificationEventArgs _
) 
'Usage
 
Dim instance As New EasyUAEventNotificationEventHandler(AddressOf HandlerMethod)
[ComVisible(false)]
public delegate void EasyUAEventNotificationEventHandler( 
   object sender,
   EasyUAEventNotificationEventArgs e
)
[ComVisible(false)]
public delegate void EasyUAEventNotificationEventHandler( 
   Object^ sender,
   EasyUAEventNotificationEventArgs^ e
)

Parameters

sender
The source of the event.
e
An OpcLabs.EasyOpc.UA.OperationModel.EasyUAEventNotificationEventArgs that contains the event data.
Example
// This example shows how to subscribe to event notifications and display each incoming event
// using a callback method that is provided as lambda expression.
//
// Find all latest examples here: https://www.doc-that.com/files/onlinedocs/OPCLabs-ConnectivityStudio/Latest/examples.html .
// OPC client and subscriber examples in C# on GitHub: https://github.com/OPCLabs/Examples-ConnectivityStudio-CSharp .
// Missing some example? Ask us for it on our Online Forums, https://forum.opclabs.com/forum/index ! You do not have to own
// a commercial license in order to use Online Forums, and we reply to every post.

using System;
using OpcLabs.EasyOpc.UA;
using OpcLabs.EasyOpc.UA.AddressSpace.Standard;

namespace UADocExamples.AlarmsAndConditions
{
    partial class SubscribeEvent
    {
        public static void CallbackLambda()
        {
            UAEndpointDescriptor endpointDescriptor =
                "opc.tcp://opcua.demo-this.com:62544/Quickstarts/AlarmConditionServer";

            // Instantiate the client object
            var client = new EasyUAClient();

            Console.WriteLine("Subscribing...");
            // The callback is a lambda expression the displays the event
            client.SubscribeEvent(
                endpointDescriptor,
                UAObjectIds.Server,
                1000,
                (sender, eventArgs) => Console.WriteLine(eventArgs));
            // Remark: Production code needs to check eventArgs.Exception before accessing eventArgs.EventData.

            Console.WriteLine("Processing event notifications for 30 seconds...");
            System.Threading.Thread.Sleep(30 * 1000);

            Console.WriteLine("Unsubscribing...");
            client.UnsubscribeAllMonitoredItems();

            Console.WriteLine("Waiting for 2 seconds...");
            System.Threading.Thread.Sleep(2 * 1000);
        }
    }
}
// This example shows how to subscribe to changes of a single monitored item, and display the value of the item with each change
// using a callback method that is provided as a function delegate.
//
// Find all latest examples here: https://www.doc-that.com/files/onlinedocs/OPCLabs-ConnectivityStudio/Latest/examples.html .
// Missing some example? Ask us for it on our Online Forums, https://forum.opclabs.com/forum/index ! You do not have to own
// a commercial license in order to use Online Forums, and we reply to every post.

module _EasyUAClient.SubscribeDataChange

open OpcLabs.EasyOpc.UA
open System
open System.Threading

let CallbackFunction =

    let endpointDescriptor =
        new UAEndpointDescriptor("opc.tcp://opcua.demo-this.com:51210/UA/SampleServer")
        // or "http://opcua.demo-this.com:51211/UA/SampleServer" (currently not supported)
        // or "https://opcua.demo-this.com:51212/UA/SampleServer/"

    // Instantiate the client object
    let client = new EasyUAClient()

    Console.WriteLine("Subscribing...");
    // The callback is a delegate that displays the value
    let handle = 
        client.SubscribeDataChange(
            endpointDescriptor,
            new UANodeDescriptor("nsu=http://test.org/UA/Data/;i=10853"),
            1000,
            new EasyUADataChangeNotificationEventHandler(
                fun sender eventArgs -> 
                    if eventArgs.Succeeded then Console.WriteLine("Value: {0}", eventArgs.AttributeData.Value)
                    else Console.WriteLine("*** Failure: {0}", eventArgs.ErrorMessageBrief)))

    Console.WriteLine("Processing data change events for 10 seconds...")
    Thread.Sleep(10 * 1000)

    Console.WriteLine("Unsubscribing...")
    client.UnsubscribeAllMonitoredItems()

    Console.WriteLine("Waiting for 2 seconds...")
    Thread.Sleep(2 * 1000)
' This example shows how to subscribe to event notifications and display each incoming event
' using a callback method that is provided as lambda expression.
'
' Find all latest examples here: https://www.doc-that.com/files/onlinedocs/OPCLabs-ConnectivityStudio/Latest/examples.html .
' OPC client and subscriber examples in VB.NET on GitHub: https://github.com/OPCLabs/Examples-ConnectivityStudio-VBNET .
' Missing some example? Ask us for it on our Online Forums, https://forum.opclabs.com/forum/index ! You do not have to own
' a commercial license in order to use Online Forums, and we reply to every post.

Imports OpcLabs.EasyOpc.UA
Imports OpcLabs.EasyOpc.UA.AddressSpace.Standard

Namespace Global.UADocExamples.AlarmsAndConditions
    Partial Friend Class SubscribeEvent
        Public Shared Sub CallbackLambda()
            ' Instantiate the client object
            Dim client = New EasyUAClient()

            Console.WriteLine("Subscribing...")
            ' The callback is a lambda expression the displays the event
            client.SubscribeEvent( _
                "opc.tcp://opcua.demo-this.com:62544/Quickstarts/AlarmConditionServer", _
                UAObjectIds.Server, _
                1000, _
                Sub(sender, eventArgs) Console.WriteLine(eventArgs))
            ' Remark: Production code would check e.Exception before accessing e.EventData.

            Console.WriteLine("Processing event notifications for 10 seconds...")
            Threading.Thread.Sleep(10 * 1000)

            Console.WriteLine("Unsubscribing...")
            client.UnsubscribeAllMonitoredItems()

            Console.WriteLine("Waiting for 2 seconds...")
            Threading.Thread.Sleep(2 * 1000)
        End Sub
    End Class
End Namespace
# This example shows how to subscribe to event notifications and display each incoming event
# using a callback method that is provided as lambda expression.
#
# Find all latest examples here: https://www.doc-that.com/files/onlinedocs/OPCLabs-ConnectivityStudio/Latest/examples.html .
# OPC client and subscriber examples in Python on GitHub: https://github.com/OPCLabs/Examples-ConnectivityStudio-Python .
# Missing some example? Ask us for it on our Online Forums, https://forum.opclabs.com/forum/index ! You do not have to own
# a commercial license in order to use Online Forums, and we reply to every post.
# The QuickOPC package is needed. Install it using "pip install opclabs_quickopc".
import opclabs_quickopc
import time

# Import .NET namespaces.
from OpcLabs.EasyOpc.UA import *
from OpcLabs.EasyOpc.UA.AddressSpace.Standard import *


# Define which server we will work with.
endpointDescriptor = UAEndpointDescriptor('opc.tcp://opcua.demo-this.com:62544/Quickstarts/AlarmConditionServer')

# Instantiate the client object.
client = EasyUAClient()

print('Subscribing...')
# The callback is a lambda expression the displays the event.
IEasyUAClientExtension.SubscribeEvent(
    client,
    endpointDescriptor,
    UANodeDescriptor(UAObjectIds.Server),
    1000,
    EasyUAEventNotificationEventHandler(lambda server, eventArgs: print(eventArgs)))
# Remark: Production code needs to check eventArgs.Exception before accessing eventArgs.EventData.

print('Processing event notifications for 30 seconds...')
time.sleep(30)

print('Unsubscribing...')
client.UnsubscribeAllMonitoredItems()

print('Waiting for 2 seconds...')
time.sleep(2)

print('Finished.')
// This example shows how to subscribe to event notifications and display each incoming event.
//
// Find all latest examples here: https://www.doc-that.com/files/onlinedocs/OPCLabs-ConnectivityStudio/Latest/examples.html .
// OPC client and subscriber examples in C# on GitHub: https://github.com/OPCLabs/Examples-ConnectivityStudio-CSharp .
// Missing some example? Ask us for it on our Online Forums, https://forum.opclabs.com/forum/index ! You do not have to own
// a commercial license in order to use Online Forums, and we reply to every post.

using System;
using OpcLabs.EasyOpc.UA;
using OpcLabs.EasyOpc.UA.AddressSpace.Standard;
using OpcLabs.EasyOpc.UA.OperationModel;

namespace UADocExamples.AlarmsAndConditions
{
    partial class SubscribeEvent
    {
        public static void Overload1()
        {
            // Define which server we will work with.
            UAEndpointDescriptor endpointDescriptor =
                "opc.tcp://opcua.demo-this.com:62544/Quickstarts/AlarmConditionServer";

            // Instantiate the client object and hook events.
            var client = new EasyUAClient();
            client.EventNotification += client_EventNotification;

            Console.WriteLine("Subscribing...");
            client.SubscribeEvent(endpointDescriptor, UAObjectIds.Server, 1000);

            Console.WriteLine("Processing event notifications for 30 seconds...");
            System.Threading.Thread.Sleep(30 * 1000);

            Console.WriteLine("Unsubscribing...");
            client.UnsubscribeAllMonitoredItems();

            Console.WriteLine("Waiting for 5 seconds...");
            System.Threading.Thread.Sleep(5 * 1000);

            Console.WriteLine("Finished.");
        }

        static void client_EventNotification(object sender, EasyUAEventNotificationEventArgs e)
        {
            // Display the event.
            Console.WriteLine(e);
        }



        // Example output (truncated):
        //Subscribing...
        //Processing event notifications for 30 seconds...
        //[] Success
        //[] Success; Refresh; RefreshInitiated
        //[] Success; Refresh; [EastTank] 100! {DialogConditionType} "The dialog was activated" @9/9/2021 2:22:18 PM (10 fields)
        //[] Success; Refresh; [EastTank] 100! {ExclusiveDeviationAlarmType} "The alarm is active." @9/9/2021 4:19:37 PM (10 fields)
        //[] Success; Refresh; [EastTank] 500! {NonExclusiveLevelAlarmType} "The alarm severity has increased." @9/9/2021 4:19:35 PM (10 fields)
        //[] Success; Refresh; [EastTank] 900! {TripAlarmType} "The alarm severity has increased." @9/9/2021 4:19:29 PM (10 fields)
        //[] Success; Refresh; [EastTank] 100! {TripAlarmType} "The alarm severity has increased." @9/9/2021 3:39:03 PM (10 fields)
        //[] Success; Refresh; [EastTank] 100! {TripAlarmType} "The alarm severity has increased." @9/9/2021 3:40:03 PM (10 fields)
        //[] Success; Refresh; [NorthMotor] 100! {DialogConditionType} "The dialog was activated" @9/9/2021 2:22:18 PM (10 fields)
        //[] Success; Refresh; [NorthMotor] 500! {ExclusiveDeviationAlarmType} "The alarm severity has increased." @9/9/2021 4:19:35 PM (10 fields)
        //[] Success; Refresh; [NorthMotor] 900! {NonExclusiveLevelAlarmType} "The alarm severity has increased." @9/9/2021 4:19:29 PM (10 fields)
        //[] Success; Refresh; [NorthMotor] 100! {TripAlarmType} "The alarm is active." @9/9/2021 4:19:32 PM (10 fields)
        //[] Success; Refresh; [NorthMotor] 100! {TripAlarmType} "The alarm severity has increased." @9/9/2021 3:39:08 PM (10 fields)
        //[] Success; Refresh; [NorthMotor] 100! {TripAlarmType} "The alarm severity has increased." @9/9/2021 3:40:14 PM (10 fields)
        //[] Success; Refresh; [WestTank] 100! {DialogConditionType} "The dialog was activated" @9/9/2021 2:22:18 PM (10 fields)
        //[] Success; Refresh; [WestTank] 900! {ExclusiveDeviationAlarmType} "The alarm severity has increased." @9/9/2021 4:19:29 PM (10 fields)
        //[] Success; Refresh; [WestTank] 100! {NonExclusiveLevelAlarmType} "The alarm is active." @9/9/2021 4:19:32 PM (10 fields)
        //[] Success; Refresh; [WestTank] 100! {TripAlarmType} "The alarm is active." @9/9/2021 4:19:37 PM (10 fields)
        //[] Success; Refresh; [WestTank] 100! {TripAlarmType} "The alarm severity has increased." @9/9/2021 3:38:55 PM (10 fields)
        //[] Success; Refresh; [WestTank] 100! {TripAlarmType} "The alarm severity has increased." @9/9/2021 3:39:43 PM (10 fields)
        //[] Success; Refresh; [SouthMotor] 100! {DialogConditionType} "The dialog was activated" @9/9/2021 2:22:18 PM (10 fields)
        //[] Success; Refresh; [SouthMotor] 100! {ExclusiveDeviationAlarmType} "The alarm is active." @9/9/2021 4:19:32 PM (10 fields)
        //[] Success; Refresh; [SouthMotor] 100! {NonExclusiveLevelAlarmType} "The alarm is active." @9/9/2021 4:19:37 PM (10 fields)
        //[] Success; Refresh; [SouthMotor] 500! {TripAlarmType} "The alarm severity has increased." @9/9/2021 4:19:35 PM (10 fields)
        //[] Success; Refresh; [SouthMotor] 100! {TripAlarmType} "The alarm severity has increased." @9/9/2021 3:39:51 PM (10 fields)
        //[] Success; Refresh; [SouthMotor] 100! {TripAlarmType} "The alarm severity has increased." @9/9/2021 3:38:57 PM (10 fields)
        //[] Success; Refresh; RefreshComplete
        //[] Success; [Internal] 500! {SystemEventType} "Raising Events" @9/9/2021 4:19:39 PM (10 fields)
        //[] Success; [Internal] 500! {AuditEventType} "Events Raised" @9/9/2021 4:19:39 PM (10 fields)
        //[] Success; [EastTank] 100! {TripAlarmType} "The alarm was deactivated by the system." @9/9/2021 4:19:39 PM (10 fields)
        //[] Success; [NorthMotor] 100! {NonExclusiveLevelAlarmType} "The alarm was deactivated by the system." @9/9/2021 4:19:39 PM (10 fields)
        //[] Success; [WestTank] 100! {ExclusiveDeviationAlarmType} "The alarm was deactivated by the system." @9/9/2021 4:19:39 PM (10 fields)
        //[] Success; [Internal] 500! {SystemEventType} "Raising Events" @9/9/2021 4:19:40 PM (10 fields)
        //[] Success; [Internal] 500! {AuditEventType} "Events Raised" @9/9/2021 4:19:40 PM (10 fields)
        //[] Success; [Internal] 500! {SystemEventType} "Raising Events" @9/9/2021 4:19:41 PM (10 fields)
        //[] Success; [Internal] 500! {AuditEventType} "Events Raised" @9/9/2021 4:19:41 PM (10 fields)
        //[] Success; [Internal] 500! {SystemEventType} "Raising Events" @9/9/2021 4:19:42 PM (10 fields)
        //[] Success; [Internal] 500! {AuditEventType} "Events Raised" @9/9/2021 4:19:42 PM (10 fields)
        //[] Success; [Internal] 500! {SystemEventType} "Raising Events" @9/9/2021 4:19:43 PM (10 fields)
        //[] Success; [NorthMotor] 300! {TripAlarmType} "The alarm severity has increased." @9/9/2021 4:19:43 PM (10 fields)
        //[] Success; [Internal] 500! {AuditEventType} "Events Raised" @9/9/2021 4:19:43 PM (10 fields)
        //[] Success; [WestTank] 300! {NonExclusiveLevelAlarmType} "The alarm severity has increased." @9/9/2021 4:19:43 PM (10 fields)
        //[] Success; [SouthMotor] 300! {ExclusiveDeviationAlarmType} "The alarm severity has increased." @9/9/2021 4:19:43 PM (10 fields)
        //[] Success; [Internal] 500! {SystemEventType} "Raising Events" @9/9/2021 4:19:44 PM (10 fields)
        //[] Success; [EastTank] 700! {NonExclusiveLevelAlarmType} "The alarm severity has increased." @9/9/2021 4:19:44 PM (10 fields)
        //[] Success; [Internal] 500! {AuditEventType} "Events Raised" @9/9/2021 4:19:44 PM (10 fields)
        //[] Success; [NorthMotor] 700! {ExclusiveDeviationAlarmType} "The alarm severity has increased." @9/9/2021 4:19:44 PM (10 fields)
        //[] Success; [SouthMotor] 700! {TripAlarmType} "The alarm severity has increased." @9/9/2021 4:19:44 PM (10 fields)
        //[] Success; [Internal] 500! {SystemEventType} "Raising Events" @9/9/2021 4:19:45 PM (10 fields)
        //[] Success; [EastTank] 300! {ExclusiveDeviationAlarmType} "The alarm severity has increased." @9/9/2021 4:19:45 PM (10 fields)
        //[] Success; [Internal] 500! {AuditEventType} "Events Raised" @9/9/2021 4:19:45 PM (10 fields)
        //...
    }
}
# This example shows how to subscribe to event notifications and display each incoming event.
#
# Find all latest examples here: https://www.doc-that.com/files/onlinedocs/OPCLabs-ConnectivityStudio/Latest/examples.html .
# OPC client and subscriber examples in PowerShell on GitHub: https://github.com/OPCLabs/Examples-ConnectivityStudio-PowerShell .
# Missing some example? Ask us for it on our Online Forums, https://forum.opclabs.com/forum/index ! You do not have to own
# a commercial license in order to use Online Forums, and we reply to every post.

#requires -Version 5.1
using namespace OpcLabs.EasyOpc.UA
using namespace OpcLabs.EasyOpc.UA.AddressSpace
using namespace OpcLabs.EasyOpc.UA.AddressSpace.Standard

# The path below assumes that the current directory is [ProductDir]/Examples-NET/PowerShell/Windows .
Add-Type -Path "../../../Components/Opclabs.QuickOpc/net472/OpcLabs.EasyOpcUAPrimitives.dll"
Add-Type -Path "../../../Components/Opclabs.QuickOpc/net472/OpcLabs.EasyOpcUACore.dll"
Add-Type -Path "../../../Components/Opclabs.QuickOpc/net472/OpcLabs.EasyOpcUA.dll"
Add-Type -Path "../../../Components/Opclabs.QuickOpc/net472/OpcLabs.EasyOpcUAComponents.dll"

# Define which server we will work with.
[UAEndpointDescriptor]$endpointDescriptor = "opc.tcp://opcua.demo-this.com:62544/Quickstarts/AlarmConditionServer"

# Instantiate the client object.
$client = New-Object EasyUAClient

# Event notification handler
Register-ObjectEvent -InputObject $client -EventName EventNotification -Action { 
    # Display the event.
    Write-Host $EventArgs
}

Write-Host "Subscribing..."
[IEasyUAClientExtension]::SubscribeEvent($client, $endpointDescriptor, [UAObjectIds]::Server, 1000)

Write-Host "Processing event notifications for 30 seconds..."
$stopwatch =  [System.Diagnostics.Stopwatch]::StartNew() 
while ($stopwatch.Elapsed.TotalSeconds -lt 30) {    
    Start-Sleep -Seconds 1
}

Write-Host "Unsubscribing..."
$client.UnsubscribeAllMonitoredItems()

Write-Host "Waiting for 5 seconds..."
Start-Sleep -Seconds 5

Write-Host "Finished."


# Example output (truncated):
#Subscribing...
#Processing event notifications for 30 seconds...
#[] Success
#[] Success; Refresh; RefreshInitiated
#[] Success; Refresh; [EastTank] 100! {DialogConditionType} "The dialog was activated" @9/9/2021 2:22:18 PM (10 fields)
#[] Success; Refresh; [EastTank] 100! {ExclusiveDeviationAlarmType} "The alarm is active." @9/9/2021 4:19:37 PM (10 fields)
#[] Success; Refresh; [EastTank] 500! {NonExclusiveLevelAlarmType} "The alarm severity has increased." @9/9/2021 4:19:35 PM (10 fields)
#[] Success; Refresh; [EastTank] 900! {TripAlarmType} "The alarm severity has increased." @9/9/2021 4:19:29 PM (10 fields)
#[] Success; Refresh; [EastTank] 100! {TripAlarmType} "The alarm severity has increased." @9/9/2021 3:39:03 PM (10 fields)
#[] Success; Refresh; [EastTank] 100! {TripAlarmType} "The alarm severity has increased." @9/9/2021 3:40:03 PM (10 fields)
#[] Success; Refresh; [NorthMotor] 100! {DialogConditionType} "The dialog was activated" @9/9/2021 2:22:18 PM (10 fields)
#[] Success; Refresh; [NorthMotor] 500! {ExclusiveDeviationAlarmType} "The alarm severity has increased." @9/9/2021 4:19:35 PM (10 fields)
#[] Success; Refresh; [NorthMotor] 900! {NonExclusiveLevelAlarmType} "The alarm severity has increased." @9/9/2021 4:19:29 PM (10 fields)
#[] Success; Refresh; [NorthMotor] 100! {TripAlarmType} "The alarm is active." @9/9/2021 4:19:32 PM (10 fields)
#[] Success; Refresh; [NorthMotor] 100! {TripAlarmType} "The alarm severity has increased." @9/9/2021 3:39:08 PM (10 fields)
#[] Success; Refresh; [NorthMotor] 100! {TripAlarmType} "The alarm severity has increased." @9/9/2021 3:40:14 PM (10 fields)
#[] Success; Refresh; [WestTank] 100! {DialogConditionType} "The dialog was activated" @9/9/2021 2:22:18 PM (10 fields)
#[] Success; Refresh; [WestTank] 900! {ExclusiveDeviationAlarmType} "The alarm severity has increased." @9/9/2021 4:19:29 PM (10 fields)
#[] Success; Refresh; [WestTank] 100! {NonExclusiveLevelAlarmType} "The alarm is active." @9/9/2021 4:19:32 PM (10 fields)
#[] Success; Refresh; [WestTank] 100! {TripAlarmType} "The alarm is active." @9/9/2021 4:19:37 PM (10 fields)
#[] Success; Refresh; [WestTank] 100! {TripAlarmType} "The alarm severity has increased." @9/9/2021 3:38:55 PM (10 fields)
#[] Success; Refresh; [WestTank] 100! {TripAlarmType} "The alarm severity has increased." @9/9/2021 3:39:43 PM (10 fields)
#[] Success; Refresh; [SouthMotor] 100! {DialogConditionType} "The dialog was activated" @9/9/2021 2:22:18 PM (10 fields)
#[] Success; Refresh; [SouthMotor] 100! {ExclusiveDeviationAlarmType} "The alarm is active." @9/9/2021 4:19:32 PM (10 fields)
#[] Success; Refresh; [SouthMotor] 100! {NonExclusiveLevelAlarmType} "The alarm is active." @9/9/2021 4:19:37 PM (10 fields)
#[] Success; Refresh; [SouthMotor] 500! {TripAlarmType} "The alarm severity has increased." @9/9/2021 4:19:35 PM (10 fields)
#[] Success; Refresh; [SouthMotor] 100! {TripAlarmType} "The alarm severity has increased." @9/9/2021 3:39:51 PM (10 fields)
#[] Success; Refresh; [SouthMotor] 100! {TripAlarmType} "The alarm severity has increased." @9/9/2021 3:38:57 PM (10 fields)
#[] Success; Refresh; RefreshComplete
#[] Success; [Internal] 500! {SystemEventType} "Raising Events" @9/9/2021 4:19:39 PM (10 fields)
#[] Success; [Internal] 500! {AuditEventType} "Events Raised" @9/9/2021 4:19:39 PM (10 fields)
#[] Success; [EastTank] 100! {TripAlarmType} "The alarm was deactivated by the system." @9/9/2021 4:19:39 PM (10 fields)
#[] Success; [NorthMotor] 100! {NonExclusiveLevelAlarmType} "The alarm was deactivated by the system." @9/9/2021 4:19:39 PM (10 fields)
#[] Success; [WestTank] 100! {ExclusiveDeviationAlarmType} "The alarm was deactivated by the system." @9/9/2021 4:19:39 PM (10 fields)
#[] Success; [Internal] 500! {SystemEventType} "Raising Events" @9/9/2021 4:19:40 PM (10 fields)
#[] Success; [Internal] 500! {AuditEventType} "Events Raised" @9/9/2021 4:19:40 PM (10 fields)
#[] Success; [Internal] 500! {SystemEventType} "Raising Events" @9/9/2021 4:19:41 PM (10 fields)
#[] Success; [Internal] 500! {AuditEventType} "Events Raised" @9/9/2021 4:19:41 PM (10 fields)
#[] Success; [Internal] 500! {SystemEventType} "Raising Events" @9/9/2021 4:19:42 PM (10 fields)
#[] Success; [Internal] 500! {AuditEventType} "Events Raised" @9/9/2021 4:19:42 PM (10 fields)
#[] Success; [Internal] 500! {SystemEventType} "Raising Events" @9/9/2021 4:19:43 PM (10 fields)
#[] Success; [NorthMotor] 300! {TripAlarmType} "The alarm severity has increased." @9/9/2021 4:19:43 PM (10 fields)
#[] Success; [Internal] 500! {AuditEventType} "Events Raised" @9/9/2021 4:19:43 PM (10 fields)
#[] Success; [WestTank] 300! {NonExclusiveLevelAlarmType} "The alarm severity has increased." @9/9/2021 4:19:43 PM (10 fields)
#[] Success; [SouthMotor] 300! {ExclusiveDeviationAlarmType} "The alarm severity has increased." @9/9/2021 4:19:43 PM (10 fields)
#[] Success; [Internal] 500! {SystemEventType} "Raising Events" @9/9/2021 4:19:44 PM (10 fields)
#[] Success; [EastTank] 700! {NonExclusiveLevelAlarmType} "The alarm severity has increased." @9/9/2021 4:19:44 PM (10 fields)
#[] Success; [Internal] 500! {AuditEventType} "Events Raised" @9/9/2021 4:19:44 PM (10 fields)
#[] Success; [NorthMotor] 700! {ExclusiveDeviationAlarmType} "The alarm severity has increased." @9/9/2021 4:19:44 PM (10 fields)
#[] Success; [SouthMotor] 700! {TripAlarmType} "The alarm severity has increased." @9/9/2021 4:19:44 PM (10 fields)
#[] Success; [Internal] 500! {SystemEventType} "Raising Events" @9/9/2021 4:19:45 PM (10 fields)
#[] Success; [EastTank] 300! {ExclusiveDeviationAlarmType} "The alarm severity has increased." @9/9/2021 4:19:45 PM (10 fields)
#[] Success; [Internal] 500! {AuditEventType} "Events Raised" @9/9/2021 4:19:45 PM (10 fields)
#...
' This example shows how to subscribe to event notifications and display each incoming event.
'
' Find all latest examples here: https://www.doc-that.com/files/onlinedocs/OPCLabs-ConnectivityStudio/Latest/examples.html .
' OPC client and subscriber examples in VB.NET on GitHub: https://github.com/OPCLabs/Examples-ConnectivityStudio-VBNET .
' Missing some example? Ask us for it on our Online Forums, https://forum.opclabs.com/forum/index ! You do not have to own
' a commercial license in order to use Online Forums, and we reply to every post.

Imports OpcLabs.EasyOpc.UA
Imports OpcLabs.EasyOpc.UA.AddressSpace.Standard
Imports OpcLabs.EasyOpc.UA.OperationModel

Namespace Global.UADocExamples.AlarmsAndConditions
    Friend Class SubscribeEvent
        Public Shared Sub Overload1()
            ' Instantiate the client object and hook events
            Dim client = New EasyUAClient()
            AddHandler client.EventNotification, AddressOf client_EventNotification

            Console.WriteLine("Subscribing...")
            client.SubscribeEvent( _
                "opc.tcp://opcua.demo-this.com:62544/Quickstarts/AlarmConditionServer", _
                UAObjectIds.Server, _
                1000)

            Console.WriteLine("Processing event notifications for 10 seconds...")
            Threading.Thread.Sleep(10 * 1000)

            Console.WriteLine("Unsubscribing...")
            client.UnsubscribeAllMonitoredItems()

            Console.WriteLine("Waiting for 5 seconds...")
            Threading.Thread.Sleep(5 * 1000)
        End Sub

        Private Shared Sub client_EventNotification(ByVal sender As Object, ByVal e As EasyUAEventNotificationEventArgs)
            ' Display the event
            Console.WriteLine(e)
        End Sub



        ' Example output (truncated):
        'Subscribing...
        'Processing event notifications for 30 seconds...
        '[] Success
        '[] Success; Refresh; RefreshInitiated
        '[] Success; Refresh; [EastTank] 100! {DialogConditionType} "The dialog was activated" @9/9/2021 2:22:18 PM (10 fields)
        '[] Success; Refresh; [EastTank] 100! {ExclusiveDeviationAlarmType} "The alarm is active." @9/9/2021 4:19:37 PM (10 fields)
        '[] Success; Refresh; [EastTank] 500! {NonExclusiveLevelAlarmType} "The alarm severity has increased." @9/9/2021 4:19:35 PM (10 fields)
        '[] Success; Refresh; [EastTank] 900! {TripAlarmType} "The alarm severity has increased." @9/9/2021 4:19:29 PM (10 fields)
        '[] Success; Refresh; [EastTank] 100! {TripAlarmType} "The alarm severity has increased." @9/9/2021 3:39:03 PM (10 fields)
        '[] Success; Refresh; [EastTank] 100! {TripAlarmType} "The alarm severity has increased." @9/9/2021 3:40:03 PM (10 fields)
        '[] Success; Refresh; [NorthMotor] 100! {DialogConditionType} "The dialog was activated" @9/9/2021 2:22:18 PM (10 fields)
        '[] Success; Refresh; [NorthMotor] 500! {ExclusiveDeviationAlarmType} "The alarm severity has increased." @9/9/2021 4:19:35 PM (10 fields)
        '[] Success; Refresh; [NorthMotor] 900! {NonExclusiveLevelAlarmType} "The alarm severity has increased." @9/9/2021 4:19:29 PM (10 fields)
        '[] Success; Refresh; [NorthMotor] 100! {TripAlarmType} "The alarm is active." @9/9/2021 4:19:32 PM (10 fields)
        '[] Success; Refresh; [NorthMotor] 100! {TripAlarmType} "The alarm severity has increased." @9/9/2021 3:39:08 PM (10 fields)
        '[] Success; Refresh; [NorthMotor] 100! {TripAlarmType} "The alarm severity has increased." @9/9/2021 3:40:14 PM (10 fields)
        '[] Success; Refresh; [WestTank] 100! {DialogConditionType} "The dialog was activated" @9/9/2021 2:22:18 PM (10 fields)
        '[] Success; Refresh; [WestTank] 900! {ExclusiveDeviationAlarmType} "The alarm severity has increased." @9/9/2021 4:19:29 PM (10 fields)
        '[] Success; Refresh; [WestTank] 100! {NonExclusiveLevelAlarmType} "The alarm is active." @9/9/2021 4:19:32 PM (10 fields)
        '[] Success; Refresh; [WestTank] 100! {TripAlarmType} "The alarm is active." @9/9/2021 4:19:37 PM (10 fields)
        '[] Success; Refresh; [WestTank] 100! {TripAlarmType} "The alarm severity has increased." @9/9/2021 3:38:55 PM (10 fields)
        '[] Success; Refresh; [WestTank] 100! {TripAlarmType} "The alarm severity has increased." @9/9/2021 3:39:43 PM (10 fields)
        '[] Success; Refresh; [SouthMotor] 100! {DialogConditionType} "The dialog was activated" @9/9/2021 2:22:18 PM (10 fields)
        '[] Success; Refresh; [SouthMotor] 100! {ExclusiveDeviationAlarmType} "The alarm is active." @9/9/2021 4:19:32 PM (10 fields)
        '[] Success; Refresh; [SouthMotor] 100! {NonExclusiveLevelAlarmType} "The alarm is active." @9/9/2021 4:19:37 PM (10 fields)
        '[] Success; Refresh; [SouthMotor] 500! {TripAlarmType} "The alarm severity has increased." @9/9/2021 4:19:35 PM (10 fields)
        '[] Success; Refresh; [SouthMotor] 100! {TripAlarmType} "The alarm severity has increased." @9/9/2021 3:39:51 PM (10 fields)
        '[] Success; Refresh; [SouthMotor] 100! {TripAlarmType} "The alarm severity has increased." @9/9/2021 3:38:57 PM (10 fields)
        '[] Success; Refresh; RefreshComplete
        '[] Success; [Internal] 500! {SystemEventType} "Raising Events" @9/9/2021 4:19:39 PM (10 fields)
        '[] Success; [Internal] 500! {AuditEventType} "Events Raised" @9/9/2021 4:19:39 PM (10 fields)
        '[] Success; [EastTank] 100! {TripAlarmType} "The alarm was deactivated by the system." @9/9/2021 4:19:39 PM (10 fields)
        '[] Success; [NorthMotor] 100! {NonExclusiveLevelAlarmType} "The alarm was deactivated by the system." @9/9/2021 4:19:39 PM (10 fields)
        '[] Success; [WestTank] 100! {ExclusiveDeviationAlarmType} "The alarm was deactivated by the system." @9/9/2021 4:19:39 PM (10 fields)
        '[] Success; [Internal] 500! {SystemEventType} "Raising Events" @9/9/2021 4:19:40 PM (10 fields)
        '[] Success; [Internal] 500! {AuditEventType} "Events Raised" @9/9/2021 4:19:40 PM (10 fields)
        '[] Success; [Internal] 500! {SystemEventType} "Raising Events" @9/9/2021 4:19:41 PM (10 fields)
        '[] Success; [Internal] 500! {AuditEventType} "Events Raised" @9/9/2021 4:19:41 PM (10 fields)
        '[] Success; [Internal] 500! {SystemEventType} "Raising Events" @9/9/2021 4:19:42 PM (10 fields)
        '[] Success; [Internal] 500! {AuditEventType} "Events Raised" @9/9/2021 4:19:42 PM (10 fields)
        '[] Success; [Internal] 500! {SystemEventType} "Raising Events" @9/9/2021 4:19:43 PM (10 fields)
        '[] Success; [NorthMotor] 300! {TripAlarmType} "The alarm severity has increased." @9/9/2021 4:19:43 PM (10 fields)
        '[] Success; [Internal] 500! {AuditEventType} "Events Raised" @9/9/2021 4:19:43 PM (10 fields)
        '[] Success; [WestTank] 300! {NonExclusiveLevelAlarmType} "The alarm severity has increased." @9/9/2021 4:19:43 PM (10 fields)
        '[] Success; [SouthMotor] 300! {ExclusiveDeviationAlarmType} "The alarm severity has increased." @9/9/2021 4:19:43 PM (10 fields)
        '[] Success; [Internal] 500! {SystemEventType} "Raising Events" @9/9/2021 4:19:44 PM (10 fields)
        '[] Success; [EastTank] 700! {NonExclusiveLevelAlarmType} "The alarm severity has increased." @9/9/2021 4:19:44 PM (10 fields)
        '[] Success; [Internal] 500! {AuditEventType} "Events Raised" @9/9/2021 4:19:44 PM (10 fields)
        '[] Success; [NorthMotor] 700! {ExclusiveDeviationAlarmType} "The alarm severity has increased." @9/9/2021 4:19:44 PM (10 fields)
        '[] Success; [SouthMotor] 700! {TripAlarmType} "The alarm severity has increased." @9/9/2021 4:19:44 PM (10 fields)
        '[] Success; [Internal] 500! {SystemEventType} "Raising Events" @9/9/2021 4:19:45 PM (10 fields)
        '[] Success; [EastTank] 300! {ExclusiveDeviationAlarmType} "The alarm severity has increased." @9/9/2021 4:19:45 PM (10 fields)
        '[] Success; [Internal] 500! {AuditEventType} "Events Raised" @9/9/2021 4:19:45 PM (10 fields)
        '...

    End Class
End Namespace
# This example shows how to subscribe to event notifications and display each incoming event.
#
# Find all latest examples here: https://www.doc-that.com/files/onlinedocs/OPCLabs-ConnectivityStudio/Latest/examples.html .
# OPC client and subscriber examples in Python on GitHub: https://github.com/OPCLabs/Examples-ConnectivityStudio-Python .
# Missing some example? Ask us for it on our Online Forums, https://forum.opclabs.com/forum/index ! You do not have to own
# a commercial license in order to use Online Forums, and we reply to every post.
# The QuickOPC package is needed. Install it using "pip install opclabs_quickopc".
import opclabs_quickopc
import time

# Import .NET namespaces.
from OpcLabs.EasyOpc.UA import *
from OpcLabs.EasyOpc.UA.AddressSpace.Standard import *
from OpcLabs.EasyOpc.UA.OperationModel import *


def eventNotification(sender, eventArgs):
    # Display the event.
    print(eventArgs)


# Define which server we will work with.
endpointDescriptor = UAEndpointDescriptor('opc.tcp://opcua.demo-this.com:62544/Quickstarts/AlarmConditionServer')

# Instantiate the client object and hook events.
client = EasyUAClient()
client.EventNotification += eventNotification

print('Subscribing...')
IEasyUAClientExtension.SubscribeEvent(
    client,
    endpointDescriptor,
    UANodeDescriptor(UAObjectIds.Server),
    1000)

print('Processing event notifications for 30 seconds...')
time.sleep(30)

print('Unsubscribing...')
client.UnsubscribeAllMonitoredItems()

print('Waiting for 5 seconds...')
time.sleep(5)

print('Finished.')
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