QuickOPC User's Guide and Reference
CategoryId Property (AECategoryElement)
Example 



OpcLabs.EasyOpcClassicCore Assembly > OpcLabs.EasyOpc.AlarmsAndEvents.AddressSpace Namespace > AECategoryElement Class : CategoryId Property
Category ID.
Syntax
'Declaration
 
<DefaultValueAttribute(0)>
<DisplayAttribute(AutoGenerateField=True, 
   Order=2, 
   ShortName="Category ID")>
<DisplayFormatAttribute("{0} (0x{0:X8})")>
Public Property CategoryId As Long
'Usage
 
Dim instance As AECategoryElement
Dim value As Long
 
instance.CategoryId = value
 
value = instance.CategoryId
[DefaultValue(0)]
[Display(AutoGenerateField=true, 
   Order=2, 
   ShortName="Category ID")]
[DisplayFormat("{0} (0x{0:X8})")]
public long CategoryId {get; set;}
[DefaultValue(0)]
[Display(AutoGenerateField=true, 
   Order=2, 
   ShortName="Category ID")]
[DisplayFormat("{0} (0x{0:X8})")]
public:
property int64 CategoryId {
   int64 get();
   void set (    int64 value);
}
Remarks

Event categories are vendor-specific. Their category IDs can be used in the event subscription for specifying filters. Category IDs are unique across the server (e.g. if Category ID x is used for both simple events and condition events, then the ID references the exact same category.)

Example

.NET

// This example shows information available about OPC event category.

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

namespace DocExamples.AlarmsAndEvents._AECategoryElement 
{ 
    class Properties 
    { 
        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 is null));

                Console.WriteLine("Information about category {0}:", categoryElement);
                Console.WriteLine("    .CategoryId: {0}", categoryElement.CategoryId);
                Console.WriteLine("    .Description: {0}", categoryElement.Description);
                Console.WriteLine("    .ConditionElements:");
                if (!(categoryElement.ConditionElements.Keys is null))
                    foreach (string conditionKey in categoryElement.ConditionElements.Keys)
                        Console.WriteLine("        {0}", conditionKey);
                Console.WriteLine("    .AttributeElements:");
                if (!(categoryElement.AttributeElements.Keys is null))
                    foreach (long attributeKey in categoryElement.AttributeElements.Keys)
                        Console.WriteLine("        {0}", attributeKey);
            }
        }
    } 
}
# This example shows information available about OPC event category.

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

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


# Instantiate the client object.
client = EasyAEClient()

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

# Display results
for categoryElement in categoryElements:
    assert categoryElement is not None
    print('Information about category ', categoryElement, sep='')
    print('    .CategoryId: ', categoryElement.CategoryId, sep='')
    print('    .Description: ', categoryElement.Description, sep='')
    print('    .ConditionElements:')
    if categoryElement.ConditionElements.Keys is not None:
        for conditionKey in categoryElement.ConditionElements.Keys:
            print('        ', conditionKey, sep='')
    print('    .AttributeElements:')
    if categoryElement.AttributeElements.Keys is not None:
        for attributeKey in categoryElement.AttributeElements.Keys:
            print('        ', attributeKey, sep='')
' This example shows information available about OPC event category.

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

Namespace AlarmsAndEvents._AECategoryElement

    Friend Class Properties
        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("Information about category {0}:", categoryElement)
                Console.WriteLine("    .CategoryId: {0}", categoryElement.CategoryId)
                Console.WriteLine("    .Description: {0}", categoryElement.Description)
                Console.WriteLine("    .ConditionElements:")
                If categoryElement.ConditionElements.Keys IsNot Nothing Then
                    For Each conditionKey As String In categoryElement.ConditionElements.Keys
                        Console.WriteLine("        {0}", conditionKey)
                    Next conditionKey
                End If
                Console.WriteLine("    .AttributeElements:")
                If categoryElement.AttributeElements.Keys IsNot Nothing Then
                    For Each attributeKey As Long In categoryElement.AttributeElements.Keys
                        Console.WriteLine("        {0}", attributeKey)
                    Next attributeKey
                End If
            Next categoryElement
        End Sub
    End Class

End Namespace
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