OPC Studio User's Guide and Reference
AEAttributeSetDictionary Class
Members  Example 



OpcLabs.EasyOpcClassicCore Assembly > OpcLabs.EasyOpc.AlarmsAndEvents Namespace : AEAttributeSetDictionary Class
This is a dictionary where the key is category ID, and the value an array of event attribute IDs for that category.
Syntax
'Usage
 
Dim instance As AEAttributeSetDictionary
Remarks

 

The EasyAEClient.QueryCategoryAttributes method finds out event attributes that the server can provide as part of an event notification within a given event category.

 

Example
// This example shows how to subscribe to events with specified event attributes, and obtain the attribute values in event 
// notifications.
//
// Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .
// OPC client and subscriber examples in C# on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-CSharp .
// Missing some example? Ask us for it on our Online Forums, https://www.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 System.Collections.Generic;
using System.Threading;
using OpcLabs.EasyOpc.AlarmsAndEvents;
using OpcLabs.EasyOpc.AlarmsAndEvents.OperationModel;
using OpcLabs.EasyOpc.DataAccess;
using OpcLabs.EasyOpc.OperationModel;

namespace DocExamples.AlarmsAndEvents._EasyAENotificationEventArgs
{
    class AttributeValues
    {
        public static void Main1()
        {
            // Instantiate the OPC-A&E client object.
            var aeClient = new EasyAEClient();

            // Instantiate the OPC-DA client object.
            var daClient = new EasyDAClient();

            var eventHandler = new EasyAENotificationEventHandler(aeClient_Notification);
            aeClient.Notification += eventHandler;

            // Inactivate the event condition (we will later activate it and receive the notification)
            daClient.WriteItemValue("", "OPCLabs.KitServer.2", "SimulateEvents.ConditionState1.Inactivate", true);

            var subscriptionFilter = new AESubscriptionFilter
            {
                Sources = new AENodeDescriptor[] { "Simulation.ConditionState1" }
            };

            // Prepare a dictionary holding requested event attributes for each event category
            // The event category IDs and event attribute IDs are hard-coded here, but can be obtained from the OPC 
            // server by querying as well.
            var returnedAttributesByCategory = new AEAttributeSetDictionary
            {
                [0x00ECFF02] = new long[] {0x00EB0003, 0x00EB0008}
            };

            Console.WriteLine("Subscribing to events...");
            int handle = aeClient.SubscribeEvents("", "OPCLabs.KitEventServer.2", 1000, null, subscriptionFilter,
                returnedAttributesByCategory);

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

            // Trigger an event carrying specified attributes (activate the condition)
            try
            {
                daClient.WriteItemValue("", "OPCLabs.KitServer.2",
                    "SimulateEvents.ConditionState1.AttributeValues.15400963", 123456);
                daClient.WriteItemValue("", "OPCLabs.KitServer.2",
                    "SimulateEvents.ConditionState1.AttributeValues.15400968", "Some string value");
                daClient.WriteItemValue("", "OPCLabs.KitServer.2", "SimulateEvents.ConditionState1.Activate", true);
            }
            catch (OpcException opcException)
            {
                Console.WriteLine("*** Failure: {0}", opcException.GetBaseException().Message);
                return;
            }

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

            aeClient.UnsubscribeEvents(handle);
        }

        // Notification event handler
        static void aeClient_Notification(object sender, EasyAENotificationEventArgs e)
        {
            if (!e.Succeeded)
            {
                Console.WriteLine("*** Failure: {0}", e.ErrorMessageBrief);
                return;
            }
            if (!e.Refresh && (!(e.EventData is null)))
            {
                // Display all received event attribute IDs and their corresponding values
                Console.WriteLine("Event attribute count: {0}", e.EventData.AttributeValues.Count);
                foreach (KeyValuePair<long, object> pair in e.EventData.AttributeValues)
                    Console.WriteLine("    {0}: {1}", pair.Key, pair.Value);
            }
        }
    }
}
' This example shows how to subscribe to events with specified event attributes, and obtain the attribute values in event 
' notifications.
'
' Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .
' OPC client and subscriber examples in VB.NET on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-VBNET .
' Missing some example? Ask us for it on our Online Forums, https://www.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 System.Threading
Imports OpcLabs.EasyOpc.AlarmsAndEvents
Imports OpcLabs.EasyOpc.AlarmsAndEvents.OperationModel
Imports OpcLabs.EasyOpc.DataAccess
Imports OpcLabs.EasyOpc.OperationModel

Namespace AlarmsAndEvents._EasyAENotificationEventArgs
    Friend Class AttributeValues
        Public Shared Sub Main1()
            Dim aeClient = New EasyAEClient()
            Dim daClient = New EasyDAClient()

            Dim eventHandler = New EasyAENotificationEventHandler(AddressOf aeClient_Notification)
            AddHandler aeClient.Notification, eventHandler

            ' Inactivate the event condition (we will later activate it and receive the notification)
            daClient.WriteItemValue("", "OPCLabs.KitServer.2", "SimulateEvents.ConditionState1.Inactivate", True)

            Dim subscriptionFilter As New AESubscriptionFilter
            subscriptionFilter.Sources = New AENodeDescriptor() {"Simulation.ConditionState1"}

            ' Prepare a dictionary holding requested event attributes for each event category
            ' The event category IDs and event attribute IDs are hard-coded here, but can be obtained from the OPC 
            ' server by querying as well.
            Dim returnedAttributesByCategory = New AEAttributeSetDictionary()
            returnedAttributesByCategory(&HECFF02) = New Long() {&HEB0003, &HEB0008}

            Console.WriteLine("Subscribing to events...")
            Dim handle As Integer = aeClient.SubscribeEvents("", "OPCLabs.KitEventServer.2", 1000, Nothing, subscriptionFilter, returnedAttributesByCategory)

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

            ' Trigger an event carrying specified attributes (activate the condition)
            Try
                daClient.WriteItemValue("", "OPCLabs.KitServer.2", "SimulateEvents.ConditionState1.AttributeValues.15400963", 123456)
                daClient.WriteItemValue("", "OPCLabs.KitServer.2", "SimulateEvents.ConditionState1.AttributeValues.15400968", "Some string value")
                daClient.WriteItemValue("", "OPCLabs.KitServer.2", "SimulateEvents.ConditionState1.Activate", True)
            Catch opcException As OpcException
                Console.WriteLine("*** Failure: {0}", opcException.GetBaseException().Message)
                Exit Sub
            End Try

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

            aeClient.UnsubscribeEvents(handle)
        End Sub

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

            If (Not e.Refresh) AndAlso (e.EventData IsNot Nothing) Then
                ' Display all received event attribute IDs and their corresponding values
                Console.WriteLine("Event attribute count: {0}", e.EventData.AttributeValues.Count)
                For Each pair As KeyValuePair(Of Long, Object) In e.EventData.AttributeValues
                    Console.WriteLine("    {0}: {1}", pair.Key, pair.Value)
                Next pair
            End If
        End Sub
    End Class
End Namespace
# This example shows how to subscribe to events with specified event attributes, and obtain the attribute values in
# event notifications.
#
# Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .
# OPC client and subscriber examples in Python on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-Python .
# Missing some example? Ask us for it on our Online Forums, https://www.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 import *
from OpcLabs.EasyOpc.AlarmsAndEvents import *
from OpcLabs.EasyOpc.DataAccess import *
from OpcLabs.EasyOpc.OperationModel import *


# Notification event handler
def notification(sender, e):
    if not e.Succeeded:
        print('*** Failure: ', e.ErrorMessageBrief, sep='')
        return
    if (not e.Refresh) and (e.EventData is not None):
        # Display all received event attribute IDs and their corresponding values.
        print('Event attribute count: ', e.EventData.AttributeValues.Count, sep='')
        for pair in e.EventData.AttributeValues:
            print('    ', pair.Key, ': ', pair.Value, sep='')


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

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

#
aeClient.Notification += notification

# Inactivate the event condition (we will later activate it and receive the notification).
try:
    IEasyDAClientExtension.WriteItemValue(daClient, '', 'OPCLabs.KitServer.2',
                                          'SimulateEvents.ConditionState1.Inactivate', True)
except OpcException as opcException:
    print('*** Failure: ' + opcException.GetBaseException().Message)
    exit()

subscriptionFilter = AESubscriptionFilter()
subscriptionFilter.Sources = [AENodeDescriptor('Simulation.ConditionState1')]

# Prepare a dictionary holding requested event attributes for each event category.
# The event category IDs and event attribute IDs are hard-coded here, but can be obtained from the OPC
# server by querying as well.
returnedAttributesByCategory = AEAttributeSetDictionary()
returnedAttributesByCategory.Add(0x00ECFF02, [0x00EB0003, 0x00EB0008])

print('Subscribing to events...')
handle = IEasyAEClientExtension.SubscribeEvents(aeClient, '', 'OPCLabs.KitEventServer.2', 1000, None,
                                                subscriptionFilter, returnedAttributesByCategory)

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

# Trigger an event carrying specified attributes (activate the condition).
try:
    IEasyDAClientExtension.WriteItemValue(daClient, '', 'OPCLabs.KitServer.2',
                                          'SimulateEvents.ConditionState1.AttributeValues.15400963', 123456)
    IEasyDAClientExtension.WriteItemValue(daClient, '', 'OPCLabs.KitServer.2',
                                          'SimulateEvents.ConditionState1.AttributeValues.15400968', 'Some string value')
    IEasyDAClientExtension.WriteItemValue(daClient, '', 'OPCLabs.KitServer.2',
                                          'SimulateEvents.ConditionState1.Activate', True)
except OpcException as opcException:
    print('*** Failure: ' + opcException.GetBaseException().Message)
    exit()

print('Processing event notifications for 10 seconds...')
time.sleep(10)

aeClient.UnsubscribeEvents(handle)
aeClient.Notification -= notification

print('Finished.')
Inheritance Hierarchy

System.Object
   System.Collections.Generic.Dictionary<TKey,TValue>
      OpcLabs.EasyOpc.AlarmsAndEvents.AEAttributeSetDictionary

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