EventNotification Method (DEasyUAClientEvents)

Raised for every event generated by a subscribed OPC monitored item.

Syntax

Visual Basic
C#
C++/CLI

'Declaration
 
<DispIdAttribute(1003)>
Sub EventNotification( _
   ByVal sender0 As Object, _
   ByVal eventArgs As EasyUAEventNotificationEventArgs _
)

'Usage
 
Dim instance As DEasyUAClientEvents
Dim sender0 As Object
Dim eventArgs As EasyUAEventNotificationEventArgs
 
instance.EventNotification(sender0, eventArgs)

[DispId(1003)]
void EventNotification( 
   object sender0,
   EasyUAEventNotificationEventArgs eventArgs
)

[DispId(1003)]
void EventNotification( 
   Object^ sender0,
   EasyUAEventNotificationEventArgs^ eventArgs
)

Parameters

sender0
eventArgs

Example

.NET

COM

.NET

COM

CSharp
PowerShell
VB.NET

// This example shows how to subscribe to event notifications and display each incoming event.
//
// Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .

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://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .

#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.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://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .

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

Namespace 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

Free Pascal
Object Pascal
PHP

// This example shows how to subscribe to event notifications and display each
// incoming event.
//
// Find all latest examples here : https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .

type
  TClientEventHandlers2 = class
    procedure OnEventNotification(
      Sender: TObject;
      sender0: OleVariant;
      eventArgs: _EasyUAEventNotificationEventArgs);
  end;

procedure TClientEventHandlers2.OnEventNotification(
  Sender: TObject;
  sender0: OleVariant;
  eventArgs: _EasyUAEventNotificationEventArgs);
begin
  // Display the event
  WriteLn(eventArgs.ToString);
end;

class procedure SubscribeEvent.Main;
var
  Client: EasyUAClient;
  EvsClient: TEvsEasyUAClient;
  ClientEventHandlers2: TClientEventHandlers2;
begin
  // Instantiate the client object and hook events
  EvsClient := TEvsEasyUAClient.Create(nil);
  Client := EvsClient.ComServer;
  ClientEventHandlers2 := TClientEventHandlers2.Create;
  EvsClient.OnEventNotification := @ClientEventHandlers2.OnEventNotification;

  WriteLn('Subscribing...');
  Client.SubscribeEvent(
    'opc.tcp://opcua.demo-this.com:62544/Quickstarts/AlarmConditionServer',
    'nsu=http://opcfoundation.org/UA/;i=2253',  // UAObjectIds.Server
    1000);

  WriteLn('Processing event notifications for 30 seconds...');
  PumpSleep(30*1000);

  WriteLn('Unsubscribing...');
  Client.UnsubscribeAllMonitoredItems;

  WriteLn('Waiting for 5 seconds...');
  PumpSleep(5*1000);
end;

// This example shows how to subscribe to event notifications and display each incoming event.
//
// Find all latest examples here : https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .

type
  TClientEventHandlers18 = class
    procedure Client_EventNotification(
      ASender: TObject;
      sender: OleVariant;
      const eventArgs: _EasyUAEventNotificationEventArgs);
  end;

procedure TClientEventHandlers18.Client_EventNotification(
  ASender: TObject;
  sender: OleVariant;
  const eventArgs: _EasyUAEventNotificationEventArgs);
begin
  // Display the event
  if eventArgs.Succeeded then
    WriteLn(eventArgs.ToString)
  else
    WriteLn(Format('*** Failure: %s', [eventArgs.ErrorMessageBrief]));
end;

class procedure SubscribeEvent.Main;
const
  UAObjectIds_Server = 'nsu=http://opcfoundation.org/UA/;i=2253';
var
  Client: TEasyUAClient;
  ClientEventHandlers: TClientEventHandlers18;
  EndpointDescriptor: string;
begin
  EndpointDescriptor := 'opc.tcp://opcua.demo-this.com:62544/Quickstarts/AlarmConditionServer';

  // Instantiate the client object and hook events
  Client := TEasyUAClient.Create(nil);
  ClientEventHandlers := TClientEventHandlers18.Create;
  Client.OnEventNotification := ClientEventHandlers.Client_EventNotification;

  WriteLn('Subscribing...');
  Client.SubscribeEvent(EndpointDescriptor, UAObjectIds_Server, 1000);

  WriteLn('Processing event notifications for 30 seconds...');
  PumpSleep(30*1000);

  WriteLn('Unsubscribing...');
  Client.UnsubscribeAllMonitoredItems;

  WriteLn('Waiting for 5 seconds...');
  Sleep(5*1000);

  WriteLn('Finished.');
  FreeAndNil(Client);
  FreeAndNil(ClientEventHandlers);

end;



// 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://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .


class ClientEvents {
    function EventNotification($Sender, $E)
    {
        // Display the event
        if ($E->Succeeded) {
            printf("%s\n", $E);
        }
        else {
            printf(" *** Failure: %s\n", $E->ErrorMessageBrief);
        }
    }
}

const UAObjectIds_Server = "nsu=http://opcfoundation.org/UA/;i=2253";

$EndpointDescriptor = "opc.tcp://opcua.demo-this.com:62544/Quickstarts/AlarmConditionServer";

// Instantiate the client object and hook events
$Client = new COM("OpcLabs.EasyOpc.UA.EasyUAClient");
$ClientEvents = new ClientEvents();
com_event_sink($Client, $ClientEvents, "DEasyUAClientEvents");

printf("Subscribing...\n");
$Client->SubscribeEvent($EndpointDescriptor, UAObjectIds_Server, 1000);

printf("Processing event notifications for 30 seconds...\n");
$startTime = time(); do { com_message_pump(1000); } while (time() < $startTime + 30);

printf("Unsubscribing...\n");
$Client->UnsubscribeAllMonitoredItems;

printf("Waiting for 5 seconds...\n");
$startTime = time(); do { com_message_pump(1000); } while (time() < $startTime + 5);



// 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)
//...

CSharp
PowerShell
VB.NET

// This example shows how to subscribe to multiple events.
//
// Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .

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

namespace UADocExamples.AlarmsAndConditions
{
    class SubscribeMultipleMonitoredItems
    {
        public static void Events()
        {
            // 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.SubscribeMultipleMonitoredItems(new[]
                {
                    new EasyUAMonitoredItemArguments("firstState", 
                        endpointDescriptor, 
                        UAObjectIds.Server,
                        new UAMonitoringParameters(1000, new UAEventFilterBuilder(
                            UAFilterElements.GreaterThanOrEqual(UABaseEventObject.Operands.Severity, 500),
                            UABaseEventObject.AllFields)))
                        { AttributeId = UAAttributeId.EventNotifier },
                    new EasyUAMonitoredItemArguments("secondState",
                        endpointDescriptor, 
                        UAObjectIds.Server,
                        new UAMonitoringParameters(2000, new UAEventFilterBuilder(
                            UAFilterElements.Equals(
                                UABaseEventObject.Operands.SourceNode, 
                                new UANodeId("nsu=http://opcfoundation.org/Quickstarts/AlarmCondition ;ns=2;s=1:Metals/SouthMotor")),
                            UABaseEventObject.AllFields)))
                        { AttributeId = UAAttributeId.EventNotifier }
                });

            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 monitored item changed events for 30 seconds...
        //[firstState] Success
        //[secondState] Success
        //[firstState] Success; Refresh; RefreshInitiated
        //[firstState] Success; Refresh; (10 field results) [EastTank] 500! "The alarm was acknoweledged." @10/14/2019 4:00:13 PM
        //[firstState] Success; Refresh; (10 field results) [EastTank] 500! "The alarm was acknoweledged." @10/14/2019 4:00:17 PM
        //[firstState] Success; Refresh; (10 field results) [NorthMotor] 500! "The alarm was acknoweledged." @10/14/2019 4:00:02 PM
        //[firstState] Success; Refresh; (10 field results) [NorthMotor] 500! "The alarm was acknoweledged." @10/14/2019 4:00:16 PM
        //[firstState] Success; Refresh; (10 field results) [SouthMotor] 700! "The alarm was acknoweledged." @10/14/2019 4:00:21 PM
        //[firstState] Success; Refresh; (10 field results) [SouthMotor] 500! "The alarm was acknoweledged." @10/14/2019 4:00:03 PM
        //[firstState] Success; Refresh; RefreshComplete
        //[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:08 PM
        //[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:08 PM
        //[secondState] Success; Refresh; RefreshInitiated
        //[secondState] Success; Refresh; (10 field results) [SouthMotor] 100! "The dialog was activated" @9/10/2019 8:08:25 PM
        //[secondState] Success; Refresh; (10 field results) [SouthMotor] 100! "The alarm is active." @11/8/2019 7:48:07 PM
        //[secondState] Success; Refresh; (10 field results) [SouthMotor] 700! "The alarm was acknoweledged." @10/14/2019 4:00:21 PM
        //[secondState] Success; Refresh; (10 field results) [SouthMotor] 500! "The alarm was acknoweledged." @10/14/2019 4:00:03 PM
        //[secondState] Success; Refresh; (10 field results) [SouthMotor] 100! "The alarm severity has increased." @9/10/2019 8:09:02 PM
        //[secondState] Success; Refresh; (10 field results) [SouthMotor] 100! "The alarm severity has increased." @9/10/2019 8:09:59 PM
        //[secondState] Success; Refresh; RefreshComplete
        //[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:09 PM
        //[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:09 PM
        //[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:10 PM
        //[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:10 PM
        //[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:11 PM
        //[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:11 PM
        //[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:12 PM
        //[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:12 PM
        //[firstState] Success; (10 field results) [EastTank] 500! "The alarm severity has increased." @11/8/2019 7:48:13 PM
        //[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:13 PM
        //[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:13 PM
        //[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:14 PM
        //[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:14 PM
        //[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:15 PM
        //[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:15 PM
        //[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:16 PM
        //[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:16 PM
        //[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:17 PM
        //[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:17 PM
        //[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:18 PM
        //[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:18 PM
        //[secondState] Success; (10 field results) [SouthMotor] 300! "The alarm severity has increased." @11/8/2019 7:48:18 PM
        //...
    }
}

# This example shows how to subscribe to multiple events.
#
# Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .

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

# The path below assumes that the current directory is [ProductDir]/Examples-NET/PowerShell/Windows .
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..."
$client.SubscribeMultipleMonitoredItems(@(
        (New-Object EasyUAMonitoredItemArguments("firstState",
            $endpointDescriptor, 
            [UAObjectIds]::Server,
            (New-Object UAMonitoringParameters(1000, [UAEventFilter](New-Object UAEventFilterBuilder(
                [UAFilterElements]::GreaterThanOrEqual([UABaseEventObject+Operands]::Severity, 500),
                [UABaseEventObject]::AllFields))))) `
            -Property @{ AttributeId = [UAAttributeId]::EventNotifier }),
        (New-Object EasyUAMonitoredItemArguments("secondState",
            $endpointDescriptor, 
            [UAObjectIds]::Server,
            (New-Object UAMonitoringParameters(2000, [UAEventFilter](New-Object UAEventFilterBuilder(
                [UAFilterElements]::Equals(
                    [UABaseEventObject+Operands]::SourceNode, 
                    (New-Object UANodeId("nsu=http://opcfoundation.org/Quickstarts/AlarmCondition ;ns=2;s=1:Metals/SouthMotor"))),
                [UABaseEventObject]::AllFields))))) `
            -Property @{ AttributeId = [UAAttributeId]::EventNotifier })
    ))

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 monitored item changed events for 30 seconds...
#[firstState] Success
#[secondState] Success
#[firstState] Success; Refresh; RefreshInitiated
#[firstState] Success; Refresh; (10 field results) [EastTank] 500! "The alarm was acknoweledged." @10/14/2019 4:00:13 PM
#[firstState] Success; Refresh; (10 field results) [EastTank] 500! "The alarm was acknoweledged." @10/14/2019 4:00:17 PM
#[firstState] Success; Refresh; (10 field results) [NorthMotor] 500! "The alarm was acknoweledged." @10/14/2019 4:00:02 PM
#[firstState] Success; Refresh; (10 field results) [NorthMotor] 500! "The alarm was acknoweledged." @10/14/2019 4:00:16 PM
#[firstState] Success; Refresh; (10 field results) [SouthMotor] 700! "The alarm was acknoweledged." @10/14/2019 4:00:21 PM
#[firstState] Success; Refresh; (10 field results) [SouthMotor] 500! "The alarm was acknoweledged." @10/14/2019 4:00:03 PM
#[firstState] Success; Refresh; RefreshComplete
#[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:08 PM
#[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:08 PM
#[secondState] Success; Refresh; RefreshInitiated
#[secondState] Success; Refresh; (10 field results) [SouthMotor] 100! "The dialog was activated" @9/10/2019 8:08:25 PM
#[secondState] Success; Refresh; (10 field results) [SouthMotor] 100! "The alarm is active." @11/8/2019 7:48:07 PM
#[secondState] Success; Refresh; (10 field results) [SouthMotor] 700! "The alarm was acknoweledged." @10/14/2019 4:00:21 PM
#[secondState] Success; Refresh; (10 field results) [SouthMotor] 500! "The alarm was acknoweledged." @10/14/2019 4:00:03 PM
#[secondState] Success; Refresh; (10 field results) [SouthMotor] 100! "The alarm severity has increased." @9/10/2019 8:09:02 PM
#[secondState] Success; Refresh; (10 field results) [SouthMotor] 100! "The alarm severity has increased." @9/10/2019 8:09:59 PM
#[secondState] Success; Refresh; RefreshComplete
#[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:09 PM
#[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:09 PM
#[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:10 PM
#[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:10 PM
#[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:11 PM
#[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:11 PM
#[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:12 PM
#[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:12 PM
#[firstState] Success; (10 field results) [EastTank] 500! "The alarm severity has increased." @11/8/2019 7:48:13 PM
#[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:13 PM
#[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:13 PM
#[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:14 PM
#[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:14 PM
#[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:15 PM
#[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:15 PM
#[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:16 PM
#[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:16 PM
#[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:17 PM
#[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:17 PM
#[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:18 PM
#[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:18 PM
#[secondState] Success; (10 field results) [SouthMotor] 300! "The alarm severity has increased." @11/8/2019 7:48:18 PM
#...

' This example shows how to subscribe to multiple events.
'
' Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .

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

Namespace AlarmsAndConditions
    Partial Friend Class SubscribeMultipleMonitoredItems
        Public Shared Sub Events()

            ' Instantiate the client object and hook events
            Dim client = New EasyUAClient()
            AddHandler client.EventNotification, AddressOf client_EventNotification

            Console.WriteLine("Subscribing...")

            client.SubscribeMultipleMonitoredItems(New EasyUAMonitoredItemArguments() _
                { _
                    New EasyUAMonitoredItemArguments("firstState", _
                        "opc.tcp://opcua.demo-this.com:62544/Quickstarts/AlarmConditionServer", _
                        UAObjectIds.Server, _
                        New UAMonitoringParameters(1000, New UAEventFilterBuilder( _
                            UAFilterElements.GreaterThanOrEqual(UABaseEventObject.Operands.Severity, 500), _
                            UABaseEventObject.AllFields))) _
                        With {.AttributeId = UAAttributeId.EventNotifier}, _
                    New EasyUAMonitoredItemArguments("secondState", _
                        "opc.tcp://opcua.demo-this.com:62544/Quickstarts/AlarmConditionServer", _
                        UAObjectIds.Server, _
                        New UAMonitoringParameters(2000, New UAEventFilterBuilder( _
                            UAFilterElements.Equals( _
                                UABaseEventObject.Operands.SourceNode, _
                                New UANodeId("nsu=http://opcfoundation.org/Quickstarts/AlarmCondition ;ns=2;s=1:Metals/SouthMotor")), _
                            UABaseEventObject.AllFields))) _
                        With {.AttributeId = UAAttributeId.EventNotifier} _
                } _
             )

            Console.WriteLine("Processing event notifications for 30 seconds...")
            Threading.Thread.Sleep(30 * 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
    End Class
End Namespace

Object Pascal
PHP
VBScript

// This example shows how to subscribe to multiple events.
//
// Find all latest examples here : https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .

type
  THelperMethods19 = class
    class function ObjectTypeIds_BaseEventType: _UANodeId; static;
    class function UAFilterElements_SimpleAttribute(TypeId: _UANodeId; simpleRelativeBrowsePathString: string): _UASimpleAttributeOperand; static;
    class function UABaseEventObject_Operands_NodeId: _UASimpleAttributeOperand; static;
    class function UABaseEventObject_Operands_EventId: _UASimpleAttributeOperand; static;
    class function UABaseEventObject_Operands_EventType: _UASimpleAttributeOperand; static;
    class function UABaseEventObject_Operands_SourceNode: _UASimpleAttributeOperand; static;
    class function UABaseEventObject_Operands_SourceName: _UASimpleAttributeOperand; static;
    class function UABaseEventObject_Operands_Time: _UASimpleAttributeOperand; static;
    class function UABaseEventObject_Operands_ReceiveTime: _UASimpleAttributeOperand; static;
    class function UABaseEventObject_Operands_LocalTime: _UASimpleAttributeOperand; static;
    class function UABaseEventObject_Operands_Message: _UASimpleAttributeOperand; static;
    class function UABaseEventObject_Operands_Severity: _UASimpleAttributeOperand; static;
    class function UABaseEventObject_AllFields: _UAAttributeFieldCollection; static;
  end;

type
  TClientEventHandlers19 = class
    procedure Client_EventNotification(
      ASender: TObject;
      sender: OleVariant;
      const eventArgs: _EasyUAEventNotificationEventArgs);
  end;

procedure TClientEventHandlers19.Client_EventNotification(
  ASender: TObject;
  sender: OleVariant;
  const eventArgs: _EasyUAEventNotificationEventArgs);
begin
  // Display the event
    WriteLn(eventArgs.ToString);
end;


class procedure SubscribeMultipleMonitoredItems.Events;
var
  Arguments: OleVariant;
  Client: TEasyUAClient;
  ClientEventHandlers: TClientEventHandlers19;
  EndpointDescriptor: string;
  EventFilter1, EventFilter2: _UAEventFilter;
  MonitoredItemArguments1, MonitoredItemArguments2: _EasyUAMonitoredItemArguments;
  MonitoringParameters1, MonitoringParameters2: _UAMonitoringParameters;
  Operand11, Operand21: _UASimpleAttributeOperand;
  Operand12, Operand22: _UALiteralOperand;
  ServerNodeId1, ServerNodeId2: _UANodeId;
  SourceNodeId: _UANodeId;
  WhereClause1, WhereClause2: _UAContentFilterElement;
begin
  EndpointDescriptor := 'opc.tcp://opcua.demo-this.com:62544/Quickstarts/AlarmConditionServer';

  // set MonitoredItemArguments1
  // Event filter: The severity is >= 500.
  Operand11 := THelperMethods19.UABaseEventObject_Operands_Severity;
  Operand12 := CoUALiteralOperand.Create;
  Operand12.Value := 500;
  WhereClause1 := CoUAContentFilterElement.Create;
  WhereClause1.FilterOperator := UAFilterOperator_GreaterThanOrEqual;
  WhereClause1.FilterOperands.Add(Operand11);
  WhereClause1.FilterOperands.Add(Operand12);

  EventFilter1 := CoUAEventFilter.Create;
  EventFilter1.SelectClauses := THelperMethods19.UABaseEventObject_AllFields;
  EventFilter1.WhereClause := WhereClause1;

  ServerNodeId1 := CoUANodeId.Create;
  ServerNodeId1.StandardName := 'Server';

  MonitoringParameters1 := CoUAMonitoringParameters.Create;
  MonitoringParameters1.EventFilter := EventFilter1;
  MonitoringParameters1.QueueSize := 1000;
  MonitoringParameters1.SamplingInterval := 1000;

  MonitoredItemArguments1 := CoEasyUAMonitoredItemArguments.Create;
  MonitoredItemArguments1.AttributeId := UAAttributeId_EventNotifier;
  MonitoredItemArguments1.EndpointDescriptor.UrlString := EndpointDescriptor;
  MonitoredItemArguments1.MonitoringParameters := MonitoringParameters1;
  MonitoredItemArguments1.NodeDescriptor.NodeId := ServerNodeId1;
  MonitoredItemArguments1.State := 'firstState';

  // set MonitoredItemArguments2
  // Event filter: The event comes from a specified source node.
  Operand21 := THelperMethods19.UABaseEventObject_Operands_SourceNode;
  SourceNodeId := CoUANodeId.Create;
  SourceNodeId.ExpandedText := 'nsu=http://opcfoundation.org/Quickstarts/AlarmCondition ;ns=2;s=1:Metals/SouthMotor';
  Operand22 := CoUALiteralOperand.Create;
  Operand22.Value := SourceNodeId;
  WhereClause2 := CoUAContentFilterElement.Create;
  WhereClause2.FilterOperator := UAFilterOperator_Equals;
  WhereClause2.FilterOperands.Add(Operand21);
  WhereClause2.FilterOperands.Add(Operand22);

  EventFilter2 := CoUAEventFilter.Create;
  EventFilter2.SelectClauses := THelperMethods19.UABaseEventObject_AllFields;
  EventFilter2.WhereClause := WhereClause2;

  ServerNodeId2 := CoUANodeId.Create;
  ServerNodeId2.StandardName := 'Server';

  MonitoringParameters2 := CoUAMonitoringParameters.Create;
  MonitoringParameters2.EventFilter := EventFilter2;
  MonitoringParameters2.QueueSize := 1000;
  MonitoringParameters2.SamplingInterval := 2000;

  MonitoredItemArguments2 := CoEasyUAMonitoredItemArguments.Create;
  MonitoredItemArguments2.AttributeId := UAAttributeId_EventNotifier;
  MonitoredItemArguments2.EndpointDescriptor.UrlString := EndpointDescriptor;
  MonitoredItemArguments2.MonitoringParameters := MonitoringParameters2;
  MonitoredItemArguments2.NodeDescriptor.NodeId := ServerNodeId2;
  MonitoredItemArguments2.State := 'secondState';


  // Instantiate the client object and hook events
  Client := TEasyUAClient.Create(nil);
  ClientEventHandlers := TClientEventHandlers19.Create;
  Client.OnEventNotification := ClientEventHandlers.Client_EventNotification;

  Arguments := VarArrayCreate([0, 1], varVariant);
  Arguments[0] := MonitoredItemArguments1;
  Arguments[1] := MonitoredItemArguments2;

  WriteLn('Subscribing...');
  Client.SubscribeMultipleMonitoredItems(Arguments);

  WriteLn('Processing monitored item changed events for 30 seconds...');
  PumpSleep(30*1000);

  WriteLn('Unsubscribing...');
  Client.UnsubscribeAllMonitoredItems;

  WriteLn('Waiting for 5 seconds...');
  Sleep(5*1000);

  WriteLn('Finished.');
  VarClear(Arguments);
  FreeAndNil(Client);
  FreeAndNil(ClientEventHandlers);
end;

class function THelperMethods19.ObjectTypeIds_BaseEventType: _UANodeId;
  var NodeId: _UANodeId;
  begin
    NodeId := CoUANodeId.Create;
    NodeId.StandardName := 'BaseEventType';
    Result := NodeId;
  end;

class function THelperMethods19.UAFilterElements_SimpleAttribute(TypeId: _UANodeId; simpleRelativeBrowsePathString: string): _UASimpleAttributeOperand;
var
  BrowsePathParser: _UABrowsePathParser;
  Operand: _UASimpleAttributeOperand;
begin
  BrowsePathParser := CoUABrowsePathParser.Create;
  Operand := CoUASimpleAttributeOperand.Create;
  Operand.TypeId.NodeId := TypeId;
  Operand.QualifiedNames := BrowsePathParser.ParseRelative(simpleRelativeBrowsePathString).ToUAQualifiedNameCollection;
  Result := Operand;
end;

class function THelperMethods19.UABaseEventObject_Operands_NodeId: _UASimpleAttributeOperand;
var
  Operand: _UASimpleAttributeOperand;
begin
  Operand := CoUASimpleAttributeOperand.Create;
  Operand.TypeId.NodeId.StandardName := 'BaseEventType';
  Operand.AttributeId := UAAttributeId_NodeId;
  Result := Operand;
end;

class function THelperMethods19.UABaseEventObject_Operands_EventId: _UASimpleAttributeOperand;
begin
  Result := UAFilterElements_SimpleAttribute(ObjectTypeIds_BaseEventType, '/EventId');
end;

class function THelperMethods19.UABaseEventObject_Operands_EventType: _UASimpleAttributeOperand;
begin
  Result := UAFilterElements_SimpleAttribute(ObjectTypeIds_BaseEventType, '/EventType');
end;

class function THelperMethods19.UABaseEventObject_Operands_SourceNode: _UASimpleAttributeOperand;
begin
  Result := UAFilterElements_SimpleAttribute(ObjectTypeIds_BaseEventType, '/SourceNode');
end;

class function THelperMethods19.UABaseEventObject_Operands_SourceName: _UASimpleAttributeOperand;
begin
  Result := UAFilterElements_SimpleAttribute(ObjectTypeIds_BaseEventType, '/SourceName');
end;

class function THelperMethods19.UABaseEventObject_Operands_Time: _UASimpleAttributeOperand;
begin
  Result := UAFilterElements_SimpleAttribute(ObjectTypeIds_BaseEventType, '/Time');
end;

class function THelperMethods19.UABaseEventObject_Operands_ReceiveTime: _UASimpleAttributeOperand;
begin
  Result := UAFilterElements_SimpleAttribute(ObjectTypeIds_BaseEventType, '/ReceiveTime');
end;

class function THelperMethods19.UABaseEventObject_Operands_LocalTime: _UASimpleAttributeOperand;
begin
  Result := UAFilterElements_SimpleAttribute(ObjectTypeIds_BaseEventType, '/LocalTime');
end;

class function THelperMethods19.UABaseEventObject_Operands_Message: _UASimpleAttributeOperand;
begin
  Result := UAFilterElements_SimpleAttribute(ObjectTypeIds_BaseEventType, '/Message');
end;

class function THelperMethods19.UABaseEventObject_Operands_Severity: _UASimpleAttributeOperand;
begin
  Result := UAFilterElements_SimpleAttribute(ObjectTypeIds_BaseEventType, '/Severity');
end;

class function THelperMethods19.UABaseEventObject_AllFields: _UAAttributeFieldCollection;
var
  Fields: _UAAttributeFieldCollection;
begin
  Fields := CoUAAttributeFieldCollection.Create;
  Fields.Add(UABaseEventObject_Operands_NodeId.ToUAAttributeField);
  Fields.Add(UABaseEventObject_Operands_EventId.ToUAAttributeField);
  Fields.Add(UABaseEventObject_Operands_EventType.ToUAAttributeField);
  Fields.Add(UABaseEventObject_Operands_SourceNode.ToUAAttributeField);
  Fields.Add(UABaseEventObject_Operands_SourceName.ToUAAttributeField);
  Fields.Add(UABaseEventObject_Operands_Time.ToUAAttributeField);
  Fields.Add(UABaseEventObject_Operands_ReceiveTime.ToUAAttributeField);
  Fields.Add(UABaseEventObject_Operands_LocalTime.ToUAAttributeField);
  Fields.Add(UABaseEventObject_Operands_Message.ToUAAttributeField);
  Fields.Add(UABaseEventObject_Operands_Severity.ToUAAttributeField);

  Result := Fields;
end;

// This example shows how to subscribe to multiple events.
//
// Find all latest examples here : https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .

const UAAttributeId_NodeId = 1;
const UAAttributeId_EventNotifier = 12;

const UAFilterOperator_Equals = 1;
const UAFilterOperator_GreaterThanOrEqual = 5;

class ClientEvents {
    function EventNotification($Sender, $E)
    {
        // Display the event
        printf("%s\n", $E);
    }
}

$EndpointDescriptor = "opc.tcp://opcua.demo-this.com:62544/Quickstarts/AlarmConditionServer";

// set MonitoredItemArguments1
// Event filter: The severity is >= 500.
$Operand11 = UABaseEventObject_Operands_Severity();
$Operand12 = new COM("OpcLabs.EasyOpc.UA.Filtering.UALiteralOperand");
$Operand12->Value = 500;
$WhereClause1 = new COM("OpcLabs.EasyOpc.UA.Filtering.UAContentFilterElement");
$WhereClause1->FilterOperator = UAFilterOperator_GreaterThanOrEqual;
$WhereClause1->FilterOperands->Add($Operand11);
$WhereClause1->FilterOperands->Add($Operand12);

$EventFilter1 = new COM("OpcLabs.EasyOpc.UA.UAEventFilter");
$EventFilter1->SelectClauses = UABaseEventObject_AllFields();
$EventFilter1->WhereClause = $WhereClause1;

$ServerNodeId1 = new COM("OpcLabs.EasyOpc.UA.AddressSpace.UANodeId");
$ServerNodeId1->StandardName = "Server";

$MonitoringParameters1 = new COM("OpcLabs.EasyOpc.UA.UAMonitoringParameters");
$MonitoringParameters1->EventFilter = $EventFilter1;
$MonitoringParameters1->QueueSize = 1000;
$MonitoringParameters1->SamplingInterval = 1000;

$MonitoredItemArguments1 = new COM("OpcLabs.EasyOpc.UA.OperationModel.EasyUAMonitoredItemArguments");
$MonitoredItemArguments1->AttributeId = UAAttributeId_EventNotifier;
$MonitoredItemArguments1->EndpointDescriptor->UrlString = $EndpointDescriptor;
$MonitoredItemArguments1->MonitoringParameters = $MonitoringParameters1;
$MonitoredItemArguments1->NodeDescriptor->NodeId = $ServerNodeId1;
$MonitoredItemArguments1->State = "firstState";

// set MonitoredItemArguments2
// Event filter: The event comes from a specified source node.
$Operand21 = UABaseEventObject_Operands_SourceNode();
$SourceNodeId = new COM("OpcLabs.EasyOpc.UA.AddressSpace.UANodeId");
$SourceNodeId->ExpandedText = "nsu=http://opcfoundation.org/Quickstarts/AlarmCondition ;ns=2;s=1:Metals/SouthMotor";
$Operand22 = new COM("OpcLabs.EasyOpc.UA.Filtering.UALiteralOperand");
$Operand22->Value = $SourceNodeId;
$WhereClause2 = new COM("OpcLabs.EasyOpc.UA.Filtering.UAContentFilterElement");
$WhereClause2->FilterOperator = UAFilterOperator_Equals;
$WhereClause2->FilterOperands->Add($Operand21);
$WhereClause2->FilterOperands->Add($Operand22);

$EventFilter2 = new COM("OpcLabs.EasyOpc.UA.UAEventFilter");
$EventFilter2->SelectClauses = UABaseEventObject_AllFields();
$EventFilter2->WhereClause = $WhereClause2;

$ServerNodeId2 = new COM("OpcLabs.EasyOpc.UA.AddressSpace.UANodeId");
$ServerNodeId2->StandardName = "Server";

$MonitoringParameters2 = new COM("OpcLabs.EasyOpc.UA.UAMonitoringParameters");
$MonitoringParameters2->EventFilter = $EventFilter2;
$MonitoringParameters2->QueueSize = 1000;
$MonitoringParameters2->SamplingInterval = 2000;

$MonitoredItemArguments2 = new COM("OpcLabs.EasyOpc.UA.OperationModel.EasyUAMonitoredItemArguments");
$MonitoredItemArguments2->AttributeId = UAAttributeId_EventNotifier;
$MonitoredItemArguments2->EndpointDescriptor->UrlString = $EndpointDescriptor;
$MonitoredItemArguments2->MonitoringParameters = $MonitoringParameters2;
$MonitoredItemArguments2->NodeDescriptor->NodeId = $ServerNodeId2;
$MonitoredItemArguments2->State = "secondState";

// Instantiate the client object and hook events
$Client = new COM("OpcLabs.EasyOpc.UA.EasyUAClient");
$ClientEvents = new ClientEvents();
com_event_sink($Client, $ClientEvents, "DEasyUAClientEvents");

$arguments[0] = $MonitoredItemArguments1;
$arguments[1] = $MonitoredItemArguments2;

printf("Subscribing...\n");
$Client->SubscribeMultipleMonitoredItems($arguments);

printf("Processing monitored item changed events for 30 seconds...\n");
$startTime = time(); do { com_message_pump(1000); } while (time() < $startTime + 30);

printf("Unsubscribing...\n");
$Client->UnsubscribeAllMonitoredItems;

printf("Waiting for 5 seconds...\n");
$startTime = time(); do { com_message_pump(1000); } while (time() < $startTime + 5);


function ObjectTypeIds_BaseEventType() {
    $NodeId = new COM("OpcLabs.EasyOpc.UA.AddressSpace.UANodeId");
    $NodeId->StandardName = "BaseEventType";
    return $NodeId;
}

function UAFilterElements_SimpleAttribute($TypeId, $simpleRelativeBrowsePathString) {
  $BrowsePathParser = new COM("OpcLabs.EasyOpc.UA.Navigation.Parsing.UABrowsePathParser");
  $Operand = new COM("OpcLabs.EasyOpc.UA.Filtering.UASimpleAttributeOperand");
  $Operand->TypeId->NodeId = $TypeId;
  $Operand->QualifiedNames = $BrowsePathParser->ParseRelative($simpleRelativeBrowsePathString)->ToUAQualifiedNameCollection;
  return $Operand;
}

function UABaseEventObject_Operands_NodeId() {
    $Operand = new COM("OpcLabs.EasyOpc.UA.Filtering.UASimpleAttributeOperand");
    $Operand->TypeId->NodeId->StandardName = "BaseEventType";
    $Operand->AttributeId = UAAttributeId_NodeId;
    return $Operand;
}

function UABaseEventObject_Operands_EventId() {
  return UAFilterElements_SimpleAttribute(ObjectTypeIds_BaseEventType(), "/EventId");
}

function UABaseEventObject_Operands_EventType() {
  return UAFilterElements_SimpleAttribute(ObjectTypeIds_BaseEventType(), "/EventType");
}

function UABaseEventObject_Operands_SourceNode() {
  return UAFilterElements_SimpleAttribute(ObjectTypeIds_BaseEventType(), "/SourceNode");
}

function UABaseEventObject_Operands_SourceName() {
  return UAFilterElements_SimpleAttribute(ObjectTypeIds_BaseEventType(), "/SourceName");
}

function UABaseEventObject_Operands_Time() {
  return UAFilterElements_SimpleAttribute(ObjectTypeIds_BaseEventType(), "/Time");
}

function UABaseEventObject_Operands_ReceiveTime() {
  return UAFilterElements_SimpleAttribute(ObjectTypeIds_BaseEventType(), "/ReceiveTime");
}

function UABaseEventObject_Operands_LocalTime() {
  return UAFilterElements_SimpleAttribute(ObjectTypeIds_BaseEventType(), "/LocalTime");
}

function UABaseEventObject_Operands_Message() {
  return UAFilterElements_SimpleAttribute(ObjectTypeIds_BaseEventType(), "/Message");
}

function UABaseEventObject_Operands_Severity() {
  return UAFilterElements_SimpleAttribute(ObjectTypeIds_BaseEventType(), "/Severity");
}


function UABaseEventObject_AllFields() {
    $Fields = new COM("OpcLabs.EasyOpc.UA.UAAttributeFieldCollection");
    $Fields->Add(UABaseEventObject_Operands_NodeId()->ToUAAttributeField);
    $Fields->Add(UABaseEventObject_Operands_EventId()->ToUAAttributeField);
    $Fields->Add(UABaseEventObject_Operands_EventType()->ToUAAttributeField);
    $Fields->Add(UABaseEventObject_Operands_SourceNode()->ToUAAttributeField);
    $Fields->Add(UABaseEventObject_Operands_SourceName()->ToUAAttributeField);
    $Fields->Add(UABaseEventObject_Operands_Time()->ToUAAttributeField);
    $Fields->Add(UABaseEventObject_Operands_ReceiveTime()->ToUAAttributeField);
    $Fields->Add(UABaseEventObject_Operands_LocalTime()->ToUAAttributeField);
    $Fields->Add(UABaseEventObject_Operands_Message()->ToUAAttributeField);
    $Fields->Add(UABaseEventObject_Operands_Severity()->ToUAAttributeField);

    return $Fields;
}

// Example output (truncated):
//Subscribing...
//Processing monitored item changed events for 30 seconds...
//[firstState] Success
//[secondState] Success
//[firstState] Success; Refresh; RefreshInitiated
//[firstState] Success; Refresh; (10 field results) [EastTank] 500! "The alarm was acknoweledged." @10/14/2019 4:00:13 PM
//[firstState] Success; Refresh; (10 field results) [EastTank] 500! "The alarm was acknoweledged." @10/14/2019 4:00:17 PM
//[firstState] Success; Refresh; (10 field results) [NorthMotor] 500! "The alarm was acknoweledged." @10/14/2019 4:00:02 PM
//[firstState] Success; Refresh; (10 field results) [NorthMotor] 500! "The alarm was acknoweledged." @10/14/2019 4:00:16 PM
//[firstState] Success; Refresh; (10 field results) [SouthMotor] 700! "The alarm was acknoweledged." @10/14/2019 4:00:21 PM
//[firstState] Success; Refresh; (10 field results) [SouthMotor] 500! "The alarm was acknoweledged." @10/14/2019 4:00:03 PM
//[firstState] Success; Refresh; RefreshComplete
//[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:08 PM
//[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:08 PM
//[secondState] Success; Refresh; RefreshInitiated
//[secondState] Success; Refresh; (10 field results) [SouthMotor] 100! "The dialog was activated" @9/10/2019 8:08:25 PM
//[secondState] Success; Refresh; (10 field results) [SouthMotor] 100! "The alarm is active." @11/8/2019 7:48:07 PM
//[secondState] Success; Refresh; (10 field results) [SouthMotor] 700! "The alarm was acknoweledged." @10/14/2019 4:00:21 PM
//[secondState] Success; Refresh; (10 field results) [SouthMotor] 500! "The alarm was acknoweledged." @10/14/2019 4:00:03 PM
//[secondState] Success; Refresh; (10 field results) [SouthMotor] 100! "The alarm severity has increased." @9/10/2019 8:09:02 PM
//[secondState] Success; Refresh; (10 field results) [SouthMotor] 100! "The alarm severity has increased." @9/10/2019 8:09:59 PM
//[secondState] Success; Refresh; RefreshComplete
//[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:09 PM
//[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:09 PM
//[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:10 PM
//[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:10 PM
//[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:11 PM
//[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:11 PM
//[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:12 PM
//[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:12 PM
//[firstState] Success; (10 field results) [EastTank] 500! "The alarm severity has increased." @11/8/2019 7:48:13 PM
//[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:13 PM
//[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:13 PM
//[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:14 PM
//[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:14 PM
//[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:15 PM
//[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:15 PM
//[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:16 PM
//[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:16 PM
//[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:17 PM
//[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:17 PM
//[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:18 PM
//[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:18 PM
//[secondState] Success; (10 field results) [SouthMotor] 300! "The alarm severity has increased." @11/8/2019 7:48:18 PM
//...

Rem This example shows how to subscribe to multiple events.
Rem
Rem Find all latest examples here : https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .

Option Explicit

Const UAAttributeId_NodeId = 1
Const UAAttributeId_EventNotifier = 12

Const UAFilterOperator_Equals = 1
Const UAFilterOperator_GreaterThanOrEqual = 5

Dim endpointDescriptor
endpointDescriptor = "opc.tcp://opcua.demo-this.com:62544/Quickstarts/AlarmConditionServer"

' Instantiate the client object and hook events
Dim Client: Set Client = CreateObject("OpcLabs.EasyOpc.UA.EasyUAClient")
WScript.ConnectObject Client, "Client_"

Dim arguments(1)
Set arguments(0) = CreateMonitoredItemArguments1
Set arguments(1) = CreateMonitoredItemArguments2

WScript.Echo "Subscribing..."
Client.SubscribeMultipleMonitoredItems arguments

WScript.Echo "Processing monitored item changed events for 30 seconds..."
WScript.Sleep 30 * 1000

WScript.Echo "Unsubscribing..."
Client.UnsubscribeAllMonitoredItems

WScript.Echo "Waiting for 5 seconds..."
WScript.Sleep 5 * 1000



Function ObjectTypeIds_BaseEventType
    Dim NodeId: Set NodeId = CreateObject("OpcLabs.EasyOpc.UA.AddressSpace.UANodeId")
    NodeId.StandardName = "BaseEventType"
    Set ObjectTypeIds_BaseEventType = NodeId
End Function

Function UAFilterElements_SimpleAttribute(TypeId, simpleRelativeBrowsePathString)
    Dim BrowsePathParser: Set BrowsePathParser = CreateObject("OpcLabs.EasyOpc.UA.Navigation.Parsing.UABrowsePathParser")
    Dim Operand: Set Operand = CreateObject("OpcLabs.EasyOpc.UA.Filtering.UASimpleAttributeOperand")
    Set Operand.TypeId.NodeId = TypeId
    Set Operand.QualifiedNames = BrowsePathParser.ParseRelative(simpleRelativeBrowsePathString).ToUAQualifiedNameCollection
    Set UAFilterElements_SimpleAttribute = Operand
End Function

Function UABaseEventObject_Operands_NodeId
    Dim Operand: Set Operand = CreateObject("OpcLabs.EasyOpc.UA.Filtering.UASimpleAttributeOperand")
    Operand.TypeId.NodeId.StandardName = "BaseEventType"
    Operand.AttributeId = UAAttributeId_NodeId
    Set UABaseEventObject_Operands_NodeId = Operand
End Function

Function UABaseEventObject_Operands_EventId
    Set UABaseEventObject_Operands_EventId = UAFilterElements_SimpleAttribute(ObjectTypeIds_BaseEventType, "/EventId")
End Function

Function UABaseEventObject_Operands_EventType
    Set UABaseEventObject_Operands_EventType = UAFilterElements_SimpleAttribute(ObjectTypeIds_BaseEventType, "/EventType")
End Function

Function UABaseEventObject_Operands_SourceNode
    Set UABaseEventObject_Operands_SourceNode = UAFilterElements_SimpleAttribute(ObjectTypeIds_BaseEventType, "/SourceNode")
End Function

Function UABaseEventObject_Operands_SourceName
    Set UABaseEventObject_Operands_SourceName = UAFilterElements_SimpleAttribute(ObjectTypeIds_BaseEventType, "/SourceName")
End Function

Function UABaseEventObject_Operands_Time
    Set UABaseEventObject_Operands_Time = UAFilterElements_SimpleAttribute(ObjectTypeIds_BaseEventType, "/Time")
End Function

Function UABaseEventObject_Operands_ReceiveTime
    Set UABaseEventObject_Operands_ReceiveTime = UAFilterElements_SimpleAttribute(ObjectTypeIds_BaseEventType, "/ReceiveTime")
End Function

Function UABaseEventObject_Operands_LocalTime
    Set UABaseEventObject_Operands_LocalTime = UAFilterElements_SimpleAttribute(ObjectTypeIds_BaseEventType, "/LocalTime")
End Function

Function UABaseEventObject_Operands_Message
    Set UABaseEventObject_Operands_Message = UAFilterElements_SimpleAttribute(ObjectTypeIds_BaseEventType, "/Message")
End Function

Function UABaseEventObject_Operands_Severity
    Set UABaseEventObject_Operands_Severity = UAFilterElements_SimpleAttribute(ObjectTypeIds_BaseEventType, "/Severity")
End Function

Function UABaseEventObject_AllFields
    Dim Fields: Set Fields = CreateObject("OpcLabs.EasyOpc.UA.UAAttributeFieldCollection")

    Fields.Add UABaseEventObject_Operands_NodeId.ToUAAttributeField

    Fields.Add UABaseEventObject_Operands_EventId.ToUAAttributeField
    Fields.Add UABaseEventObject_Operands_EventType.ToUAAttributeField
    Fields.Add UABaseEventObject_Operands_SourceNode.ToUAAttributeField
    Fields.Add UABaseEventObject_Operands_SourceName.ToUAAttributeField
    Fields.Add UABaseEventObject_Operands_Time.ToUAAttributeField
    Fields.Add UABaseEventObject_Operands_ReceiveTime.ToUAAttributeField
    Fields.Add UABaseEventObject_Operands_LocalTime.ToUAAttributeField
    Fields.Add UABaseEventObject_Operands_Message.ToUAAttributeField
    Fields.Add UABaseEventObject_Operands_Severity.ToUAAttributeField

    Set UABaseEventObject_AllFields = Fields
End Function

Function CreateMonitoredItemArguments1
    ' Event filter: The severity is >= 500.
    Dim Operand1: Set Operand1 = UABaseEventObject_Operands_Severity
    Dim Operand2: Set Operand2 = CreateObject("OpcLabs.EasyOpc.UA.Filtering.UALiteralOperand")
    Operand2.Value = 500
    Dim WhereClause: Set WhereClause = CreateObject("OpcLabs.EasyOpc.UA.Filtering.UAContentFilterElement")
    WhereClause.FilterOperator = UAFilterOperator_GreaterThanOrEqual
    WhereClause.FilterOperands.Add Operand1
    WhereClause.FilterOperands.Add Operand2

    Dim EventFilter: Set EventFilter = CreateObject("OpcLabs.EasyOpc.UA.UAEventFilter")
    Set EventFilter.SelectClauses = UABaseEventObject_AllFields
    Set EventFilter.WhereClause = WhereClause

    Dim ServerNodeId: Set ServerNodeId = CreateObject("OpcLabs.EasyOpc.UA.AddressSpace.UANodeId")
    ServerNodeId.StandardName = "Server"

    Dim MonitoringParameters: Set MonitoringParameters = CreateObject("OpcLabs.EasyOpc.UA.UAMonitoringParameters")
    Set MonitoringParameters.EventFilter = EventFilter
    MonitoringParameters.QueueSize = 1000
    MonitoringParameters.SamplingInterval = 1000

    Dim MonitoredItemArguments: Set MonitoredItemArguments = CreateObject("OpcLabs.EasyOpc.UA.OperationModel.EasyUAMonitoredItemArguments")
    MonitoredItemArguments.AttributeId = UAAttributeId_EventNotifier
    MonitoredItemArguments.EndpointDescriptor.UrlString = endpointDescriptor
    Set MonitoredItemArguments.MonitoringParameters = MonitoringParameters
    Set MonitoredItemArguments.NodeDescriptor.NodeId = ServerNodeId
    MonitoredItemArguments.State = "firstState"

    Set CreateMonitoredItemArguments1 = MonitoredItemArguments
End Function

Function CreateMonitoredItemArguments2
    ' Event filter: The event comes from a specified source node.
    Dim Operand1: Set Operand1 = UABaseEventObject_Operands_SourceNode
    Dim SourceNodeId: Set SourceNodeId = CreateObject("OpcLabs.EasyOpc.UA.AddressSpace.UANodeId")
    SourceNodeId.ExpandedText = "nsu=http://opcfoundation.org/Quickstarts/AlarmCondition ;ns=2;s=1:Metals/SouthMotor"
    Dim Operand2: Set Operand2 = CreateObject("OpcLabs.EasyOpc.UA.Filtering.UALiteralOperand")
    Set Operand2.Value = SourceNodeId
    Dim WhereClause: Set WhereClause = CreateObject("OpcLabs.EasyOpc.UA.Filtering.UAContentFilterElement")
    WhereClause.FilterOperator = UAFilterOperator_Equals
    WhereClause.FilterOperands.Add Operand1
    WhereClause.FilterOperands.Add Operand2

    Dim EventFilter: Set EventFilter = CreateObject("OpcLabs.EasyOpc.UA.UAEventFilter")
    Set EventFilter.SelectClauses = UABaseEventObject_AllFields
    Set EventFilter.WhereClause = WhereClause

    Dim ServerNodeId: Set ServerNodeId = CreateObject("OpcLabs.EasyOpc.UA.AddressSpace.UANodeId")
    ServerNodeId.StandardName = "Server"

    Dim MonitoringParameters: Set MonitoringParameters = CreateObject("OpcLabs.EasyOpc.UA.UAMonitoringParameters")
    Set MonitoringParameters.EventFilter = EventFilter
    MonitoringParameters.QueueSize = 1000
    MonitoringParameters.SamplingInterval = 2000

    Dim MonitoredItemArguments: Set MonitoredItemArguments = CreateObject("OpcLabs.EasyOpc.UA.OperationModel.EasyUAMonitoredItemArguments")
    MonitoredItemArguments.AttributeId = UAAttributeId_EventNotifier
    MonitoredItemArguments.EndpointDescriptor.UrlString = endpointDescriptor
    Set MonitoredItemArguments.MonitoringParameters = MonitoringParameters
    Set MonitoredItemArguments.NodeDescriptor.NodeId = ServerNodeId
    MonitoredItemArguments.State = "secondState"

    Set CreateMonitoredItemArguments2 = MonitoredItemArguments
End Function

Sub Client_EventNotification(Sender, e)
    ' Display the event
    WScript.Echo e
End Sub



' Example output (truncated):
'Subscribing...
'Processing monitored item changed events for 30 seconds...
'[firstState] Success
'[secondState] Success
'[firstState] Success; Refresh; RefreshInitiated
'[firstState] Success; Refresh; (10 field results) [EastTank] 500! "The alarm was acknoweledged." @10/14/2019 4:00:13 PM
'[firstState] Success; Refresh; (10 field results) [EastTank] 500! "The alarm was acknoweledged." @10/14/2019 4:00:17 PM
'[firstState] Success; Refresh; (10 field results) [NorthMotor] 500! "The alarm was acknoweledged." @10/14/2019 4:00:02 PM
'[firstState] Success; Refresh; (10 field results) [NorthMotor] 500! "The alarm was acknoweledged." @10/14/2019 4:00:16 PM
'[firstState] Success; Refresh; (10 field results) [SouthMotor] 700! "The alarm was acknoweledged." @10/14/2019 4:00:21 PM
'[firstState] Success; Refresh; (10 field results) [SouthMotor] 500! "The alarm was acknoweledged." @10/14/2019 4:00:03 PM
'[firstState] Success; Refresh; RefreshComplete
'[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:08 PM
'[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:08 PM
'[secondState] Success; Refresh; RefreshInitiated
'[secondState] Success; Refresh; (10 field results) [SouthMotor] 100! "The dialog was activated" @9/10/2019 8:08:25 PM
'[secondState] Success; Refresh; (10 field results) [SouthMotor] 100! "The alarm is active." @11/8/2019 7:48:07 PM
'[secondState] Success; Refresh; (10 field results) [SouthMotor] 700! "The alarm was acknoweledged." @10/14/2019 4:00:21 PM
'[secondState] Success; Refresh; (10 field results) [SouthMotor] 500! "The alarm was acknoweledged." @10/14/2019 4:00:03 PM
'[secondState] Success; Refresh; (10 field results) [SouthMotor] 100! "The alarm severity has increased." @9/10/2019 8:09:02 PM
'[secondState] Success; Refresh; (10 field results) [SouthMotor] 100! "The alarm severity has increased." @9/10/2019 8:09:59 PM
'[secondState] Success; Refresh; RefreshComplete
'[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:09 PM
'[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:09 PM
'[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:10 PM
'[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:10 PM
'[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:11 PM
'[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:11 PM
'[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:12 PM
'[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:12 PM
'[firstState] Success; (10 field results) [EastTank] 500! "The alarm severity has increased." @11/8/2019 7:48:13 PM
'[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:13 PM
'[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:13 PM
'[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:14 PM
'[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:14 PM
'[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:15 PM
'[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:15 PM
'[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:16 PM
'[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:16 PM
'[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:17 PM
'[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:17 PM
'[firstState] Success; (10 field results) [Internal] 500! "Raising Events" @11/8/2019 7:48:18 PM
'[firstState] Success; (10 field results) [Internal] 500! "Events Raised" @11/8/2019 7:48:18 PM
'[secondState] Success; (10 field results) [SouthMotor] 300! "The alarm severity has increased." @11/8/2019 7:48:18 PM
'...

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

DEasyUAClientEvents Interface
DEasyUAClientEvents Members

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