Examples - OPC Alarms&Events - Query for event categories

.NET

// This example shows how to enumerate all event categories provided by the OPC server. For each category, it displays its Id 
// and description.

using System;
using System.Diagnostics;
using OpcLabs.EasyOpc.AlarmsAndEvents;
using OpcLabs.EasyOpc.AlarmsAndEvents.AddressSpace;
using OpcLabs.EasyOpc.OperationModel;

namespace DocExamples.AlarmsAndEvents._EasyAEClient
{
    class QueryEventCategories 
    { 
        public static void Main1()
        {
            // Instantiate the client object.
            var client = new EasyAEClient();

            AECategoryElementCollection categoryElements;
            try
            {
                categoryElements = client.QueryEventCategories("", "OPCLabs.KitEventServer.2");
            }
            catch (OpcException opcException)
            {
                Console.WriteLine("*** Failure: {0}", opcException.GetBaseException().Message);
                return;
            }

            foreach (AECategoryElement categoryElement in categoryElements)
            {
                Debug.Assert(categoryElement != null);
                Console.WriteLine("CategoryElements[\"{0}\"].Description: {1}", categoryElement.CategoryId, categoryElement.Description);
            }
        }
    } 
}

# This example shows how to enumerate all event categories provided by the OPC server. For each category, it displays
# its Id and description.

# The QuickOPC package is needed. Install it using "pip install opclabs_quickopc".
import opclabs_quickopc

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


# Instantiate the client object
client = EasyAEClient()

# Perform the operation
try:
    categoryElements = IEasyAEClientExtension.QueryEventCategories(client, '', 'OPCLabs.KitEventServer.2')
except OpcException as opcException:
    print('*** Failure: ' + opcException.GetBaseException().Message)
    exit()

# Display results
for categoryElement in categoryElements:
    assert categoryElement is not None
    print('CategoryElements[', categoryElement.CategoryId, '].Description: ', categoryElement.Description, sep='')

' This example shows how to enumerate all event categories provided by the OPC server. For each category, it displays its Id 
' and description.

Imports OpcLabs.EasyOpc.AlarmsAndEvents
Imports OpcLabs.EasyOpc.AlarmsAndEvents.AddressSpace
Imports OpcLabs.EasyOpc.OperationModel

Namespace AlarmsAndEvents._EasyAEClient

    Friend Class QueryEventCategories
        Public Shared Sub Main1()
            Dim client = New EasyAEClient()

            Dim categoryElements As AECategoryElementCollection
            Try
                categoryElements = client.QueryEventCategories("", "OPCLabs.KitEventServer.2")
            Catch opcException As OpcException
                Console.WriteLine("*** Failure: {0}", opcException.GetBaseException().Message)
                Exit Sub
            End Try

            For Each categoryElement As AECategoryElement In categoryElements
                Debug.Assert(categoryElement IsNot Nothing)
                Console.WriteLine("CategoryElements[""{0}""].Description: {1}", categoryElement.CategoryId, categoryElement.Description)
            Next categoryElement
        End Sub
    End Class

End Namespace

COM

VBScript

Rem This example shows how to enumerate all event categories provided by the OPC server. For each category, it displays its Id 
Rem and description.

Option Explicit

Const AEEventTypes_All = 7

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

Dim Client: Set Client = CreateObject("OpcLabs.EasyOpc.AlarmsAndEvents.EasyAEClient")
On Error Resume Next
Dim CategoryElements: Set CategoryElements = Client.QueryEventCategories(ServerDescriptor, AEEventTypes_All)
If Err.Number <> 0 Then
    WScript.Echo "*** Failure: " & Err.Source & ": " & Err.Description
    WScript.Quit
End If
On Error Goto 0

Dim CategoryElement: For Each CategoryElement In CategoryElements
    WScript.Echo "CategoryElements(" & CategoryElement.CategoryId & ").Description: " & CategoryElement.Description
Next

Conceptual

Querying for OPC A&E Event Categories