Querying for OPC A&E Event Conditions on a Source

The EasyAEClient.QuerySourceConditions method finds out event conditions associated with the given event source.

.NET

// This example shows how to enumerate all event conditions associated with the specified event source.

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

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

            AEConditionElementCollection conditionElements;
            try
            {
                conditionElements = client.QuerySourceConditions("", "OPCLabs.KitEventServer.2", 
                    "Simulation.ConditionState1");
            }
            catch (OpcException opcException)
            {
                Console.WriteLine("*** Failure: {0}", opcException.GetBaseException().Message);
                return;
            }

            foreach (AEConditionElement conditionElement in conditionElements)
            {
                Debug.Assert(conditionElement != null);
                Console.WriteLine("ConditionElements[\"{0}\"]: {1} subcondition(s)", 
                    conditionElement.Name, conditionElement.SubconditionNames.Length);
            }
        }
    } 
}

# This example shows how to enumerate all event conditions associated with the specified event source.

# 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:
    conditionElements = IEasyAEClientExtension.QuerySourceConditions(client, '', 'OPCLabs.KitEventServer.2',
                                                                     AENodeDescriptor('Simulation.ConditionState1'))
except OpcException as opcException:
    print('*** Failure: ' + opcException.GetBaseException().Message)
    exit()

# Display results.
for conditionElement in conditionElements:
    assert conditionElement is not None
    print('ConditionElements[', conditionElement.Name, ']: ',
          conditionElement.SubconditionNames.Length, ' subcondition(s)',
          sep='')

print()
print('Finished.')

' This example shows how to enumerate all event conditions associated with the specified event source.

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

Namespace AlarmsAndEvents._EasyAEClient

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

            Dim conditionElements As AEConditionElementCollection
            Try
                conditionElements = client.QuerySourceConditions( _
                    "", "OPCLabs.KitEventServer.2", "Simulation.ConditionState1")
            Catch opcException As OpcException
                Console.WriteLine("*** Failure: {0}", opcException.GetBaseException().Message)
                Exit Sub
            End Try

            For Each conditionElement As AEConditionElement In conditionElements
                Debug.Assert(conditionElement IsNot Nothing)
                Console.WriteLine("ConditionElements[""{0}""]: {1} subcondition(s)", _
                                  conditionElement.Name, conditionElement.SubconditionNames.Length)
            Next conditionElement
        End Sub
    End Class

End Namespace

COM

VBScript

Rem This example shows how to enumerate all event conditions associated with the specified event source.

Option Explicit

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

Dim SourceDescriptor: Set SourceDescriptor = CreateObject("OpcLabs.EasyOpc.AlarmsAndEvents.AENodeDescriptor")
SourceDescriptor.QualifiedName = "Simulation.ConditionState1"

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

Dim ConditionElement: For Each ConditionElement In ConditionElements
    WScript.Echo "ConditionElements(" & ConditionElement.Name & "): " & (UBound(ConditionElement.SubconditionNames) + 1) & " subcondition(s)"
Next