OPC Studio User's Guide and Reference
AEConditionState Class
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OpcLabs.EasyOpcClassicCore Assembly > OpcLabs.EasyOpc.AlarmsAndEvents Namespace : AEConditionState Class
Contains current state information about an OPC condition instance.
Object Model
AEConditionState ClassAESubconditionElement ClassAEAttributeValueDictionary ClassDAQuality ClassDAQuality ClassAESubconditionElementCollection ClassAESubconditionElement Class
Syntax
'Declaration
 
<CLSCompliantAttribute(True)>
<ComDefaultInterfaceAttribute(OpcLabs.EasyOpc.AlarmsAndEvents.ComTypes._AEConditionState)>
<ComVisibleAttribute(True)>
<GuidAttribute("2FF5B789-FCF1-4321-A4D5-2D5BB2E0B341")>
<TypeConverterAttribute(System.ComponentModel.ExpandableObjectConverter)>
<ValueControlAttribute("OpcLabs.BaseLib.Forms.Common.ObjectSerializationControl, OpcLabs.BaseLibForms, Version=5.81.455.1, Culture=neutral, PublicKeyToken=6faddca41dacb409", 
   DefaultReadWrite=False, 
   Export=True, 
   PageId=10001)>
<SerializableAttribute()>
Public NotInheritable Class AEConditionState 
   Inherits OpcLabs.BaseLib.Info
   Implements LINQPad.ICustomMemberProvider, OpcLabs.BaseLib.ComTypes._Info, OpcLabs.BaseLib.ComTypes._Object2, OpcLabs.EasyOpc.AlarmsAndEvents.ComTypes._AEConditionState, System.ICloneable, System.Runtime.Serialization.ISerializable, System.Xml.Serialization.IXmlSerializable 
 
'Usage
 
Dim instance As AEConditionState
Remarks

 

In OPC Alarms and Events, information is usually provided in form of event notifications, especially for transient (simple and tracking) events. For condition-related events, however, it is also possible to get (upon request) information about the current state of a specified condition.

If you want to obtain the current state information for the condition instance in an OPC Alarms and Events sever, call the GetConditionState method. You pass in individual arguments for machine name, server class, fully qualified source name, condition name, and optionally an array of event attributes to be returned. You will receive back an AEConditionState object holding the current state information about an OPC condition instance.

.NET

// This example shows how to obtain current state information for the condition instance corresponding to a Source and 
// certain ConditionName.
//
// 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 OpcLabs.EasyOpc.AlarmsAndEvents;
using OpcLabs.EasyOpc.OperationModel;

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

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

            Console.WriteLine("ConditionState:");
            Console.WriteLine("    .ActiveSubcondition: {0}", conditionState.ActiveSubcondition);
            Console.WriteLine("    .Enabled: {0}", conditionState.Enabled);
            Console.WriteLine("    .Active: {0}", conditionState.Active);
            Console.WriteLine("    .Acknowledged: {0}", conditionState.Acknowledged);
            Console.WriteLine("    .Quality: {0}", conditionState.Quality);
            // Remark: IAEConditionState has many more properties
        }
    } 
}

COM

# This example shows how to obtain current state information for the condition instance corresponding to a Source and 
# certain ConditionName.
#
# The Python for Windows (pywin32) extensions package is needed. Install it using "pip install pypiwin32".
# CAUTION: We now recommend using Python.NET package instead. Full set of examples with Python.NET is available!
#
# Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .
import time
import win32com.client
from pywintypes import com_error

serverDescriptor = win32com.client.Dispatch('OpcLabs.EasyOpc.ServerDescriptor')
serverDescriptor.UrlString = 'opcae://localhost/OPCLabs.KitEventServer.2'
#serverDescriptor.ServerClass = 'OPCLabs.KitEventServer.2'

sourceDescriptor = win32com.client.Dispatch('OpcLabs.EasyOpc.AlarmsAndEvents.AENodeDescriptor')
sourceDescriptor.QualifiedName = "Simulation.ConditionState1"

# Instantiate the client object
client = win32com.client.Dispatch('OpcLabs.EasyOpc.AlarmsAndEvents.EasyAEClient') 

print('Getting condition state...')
try:
    conditionState = client.GetConditionState(serverDescriptor, sourceDescriptor, 'Simulated', [])
except com_error as e:
    print('*** Failure: ' + e.args[2][1] + ': ' + e.args[2][2])
    exit()

print('ConditionState:')
print('    .ActiveSubcondition: ', conditionState.ActiveSubcondition)
print('    .Enabled: ', conditionState.Enabled)
print('    .Active: ', conditionState.Active)
print('    .Acknowledged: ', conditionState.Acknowledged)
print('    .Quality: ', conditionState.Quality)
# Note that IAEConditionState has many more properties

print()
print('Finished.')

Python

# This example shows how to obtain current state information for the condition instance corresponding to a Source and 
# certain ConditionName.
#
# 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 .NET namespaces.
from OpcLabs.EasyOpc import *
from OpcLabs.EasyOpc.AlarmsAndEvents import *
from OpcLabs.EasyOpc.OperationModel import *


# Instantiate the client object
client = EasyAEClient()

print('Getting condition state...')
try:
    conditionState = IEasyAEClientExtension.GetConditionState(client,
        '', 'OPCLabs.KitEventServer.2', 'Simulation.ConditionState1', 'Simulated')
except OpcException as opcException:
    print('*** Failure: ' + opcException.GetBaseException().Message)
    exit()

print('ConditionState:')
print('    .ActiveSubcondition: ', conditionState.ActiveSubcondition)
print('    .Enabled: ', conditionState.Enabled)
print('    .Active: ', conditionState.Active)
print('    .Acknowledged: ', conditionState.Acknowledged)
print('    .Quality: ', conditionState.Quality)
# Note that IAEConditionState has many more properties

print()
print('Finished.')

 

 

In QuickOPC.NET, you can alternatively pass in a ServerDescriptor in place of machine name and server class arguments.

 

 

Inheritance Hierarchy

System.Object
   OpcLabs.BaseLib.Object2
      OpcLabs.BaseLib.Info
         OpcLabs.EasyOpc.AlarmsAndEvents.AEConditionState

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