Connectivity Software User's Guide and Reference
EasyUADataSetFieldMessageEventArgs Class
Members  Example 



OpcLabs.EasyOpcUAPrimitives Assembly > OpcLabs.EasyOpc.UA.PubSub.OperationModel Namespace : EasyUADataSetFieldMessageEventArgs Class
Event arguments for the EasyUASubscribeDataSetFieldArguments.Callback method.
Object Model
EasyUADataSetFieldMessageEventArgs ClassEasyUASubscribeDataSetFieldArguments ClassExceptionCollection ClassUADataSetFieldData ClassNormalizedExceptionCollection ClassNormalizedException ClassNormalizedException ClassUAPubSubLocators ClassUADataSetSubscriptionDescriptor Class
Syntax
'Usage
 
Dim instance As EasyUADataSetFieldMessageEventArgs
Remarks

Not available in COM.

Some information available through the EasyUADataSetMessageEventArgs.DataSetData, such as OpcLabs.EasyOpc.UA.PubSub.UAPubSubHeader.ConfigurationVersion, is not available through this event. This is intentional. If you need such information, subscribe to the whole dataset instead.

Example
// This example shows how to subscribe to a single dataset field, resolving logical parameters to physical from an OPC-UA
// PubSub configuration file in binary format. The metadata obtained through the resolution is used to decode fixed layout
// messages with RawData field encoding.
//
// In order to produce network messages for this example, run the UADemoPublisher tool. For documentation, see
// https://kb.opclabs.com/UADemoPublisher_Basics . In some cases, you may have to specify the interface name to be used.
//
// Find all latest examples here: https://www.doc-that.com/files/onlinedocs/OPCLabs-ConnectivityStudio/Latest/examples.html .
// OPC client and subscriber examples in C# on GitHub: https://github.com/OPCLabs/Examples-ConnectivityStudio-CSharp .
// Missing some example? Ask us for it on our Online Forums, https://forum.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.Threading;
using OpcLabs.EasyOpc.UA.PubSub;

namespace UASubscriberDocExamples.PubSub._EasyUASubscriber
{
    class SubscribeDataSetField
    {
        public static void Main1()
        {
            // Define the PubSub resolver. We want the information be resolved from a PubSub binary configuration file that
            // we have. The file itself at the root of the project, and we have specified that it has to be copied to the
            // project's output directory.
            var pubSubResolverDescriptor = UAPubSubResolverDescriptor.File("UADemoPublisher-Default.uabinary");

            // Define the PubSub connection we will work with, using its logical name in the PubSub configuration.
            var pubSubConnectionDescriptor = new UAPubSubConnectionDescriptor { Name = "FixedLayoutConnection" };
            // In some cases you may have to set the interface (network adapter) name that needs to be used, similarly to
            // the statement below. Your actual interface name may differ, of course.
            //pubSubConnectionDescriptor.ResourceAddress.InterfaceName = "Ethernet";

            // Define the filter. The writer group and the dataset writer are specified using their logical names in the
            // PubSub configuration. The publisher Id in the filter will be taken from the logical PubSub connection.
            var filter = new UASubscribeDataSetFilter("FixedLayoutGroup", "SimpleWriter");

            // Instantiate the subscriber object.
            var subscriber = new EasyUASubscriber();

            Console.WriteLine("Subscribing...");
            int fieldHandle = subscriber.SubscribeDataSetField(
                pubSubResolverDescriptor, 
                pubSubConnectionDescriptor,
                filter,
                "Int32Fast",
                (sender, args) => { Console.WriteLine(args); });

            Console.WriteLine("Processing dataset message events for 20 seconds...");
            Thread.Sleep(20 * 1000);

            Console.WriteLine("Unsubscribing...");
            subscriber.UnsubscribeDataSetField(fieldHandle);

            Console.WriteLine("Waiting for 1 second...");
            // Unsubscribe operation is asynchronous, messages may still come for a short while.
            Thread.Sleep(1 * 1000);

            Console.WriteLine("Finished.");
        }

        // Example output:
        //
        //Subscribing...
        //Processing dataset message events for 20 seconds...
        //Success
        //Success; 1626 {System.Int32}; Good
        //Success; 1711 {System.Int32}; Good
        //Success; 1741 {System.Int32}; Good
        //Success; 1837 {System.Int32}; Good
        //Success; 1897 {System.Int32}; Good
        //Success; 1993 {System.Int32}; Good
        //Success; 2082 {System.Int32}; Good
        //Success; 2135 {System.Int32}; Good
        //Success; 2185 {System.Int32}; Good
        //Success; 2241 {System.Int32}; Good
        //Success; 2324 {System.Int32}; Good
        //Success; 2368 {System.Int32}; Good
        //Success; 2423 {System.Int32}; Good
        //Success; 2445 {System.Int32}; Good
        //Success; 2497 {System.Int32}; Good
        //Success; 2584 {System.Int32}; Good
        //Success; 2608 {System.Int32}; Good
        //...
    }
}
' This example shows how to subscribe to a single dataset field, resolving logical parameters to physical from an OPC-UA
' PubSub configuration file in binary format. The metadata obtained through the resolution is used to decode fixed layout
' messages with RawData field encoding.
'
' In order to produce network messages for this example, run the UADemoPublisher tool. For documentation, see
' https://kb.opclabs.com/UADemoPublisher_Basics . In some cases, you may have to specify the interface name to be used.
'
' Find all latest examples here: https://www.doc-that.com/files/onlinedocs/OPCLabs-ConnectivityStudio/Latest/examples.html .
' OPC client and subscriber examples in VB.NET on GitHub: https://github.com/OPCLabs/Examples-ConnectivityStudio-VBNET .
' Missing some example? Ask us for it on our Online Forums, https://forum.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 OpcLabs.EasyOpc.UA.PubSub

Namespace Global.UASubscriberDocExamples.PubSub._EasyUASubscriber
    Friend Class SubscribeDataSetField
        Public Shared Sub Main1()

            ' Define the PubSub resolver. We want the information be resolved from a PubSub binary configuration file that
            ' we have. The file itself is at the root of the project, and we have specified that it has to be copied to the
            ' project's output directory.
            Dim pubSubResolverDescriptor = UAPubSubResolverDescriptor.File("UADemoPublisher-Default.uabinary")

            ' Define the PubSub connection we will work with, using its logical name in the PubSub configuration.
            Dim pubSubConnectionDescriptor = New UAPubSubConnectionDescriptor
            pubSubConnectionDescriptor.Name = "FixedLayoutConnection"
            ' In some cases you may have to set the interface (network adapter) name that needs to be used, similarly to
            ' the statement below. Your actual interface name may differ, of course.
            ' pubSubConnectionDescriptor.ResourceAddress.InterfaceName = "Ethernet"

            ' Define the filter. The writer group and the dataset writer are specified using their logical names in the
            ' PubSub configuration. The publisher Id in the filter will be taken from the logical PubSub connection.
            Dim filter = New UASubscribeDataSetFilter("FixedLayoutGroup", "SimpleWriter")

            ' Instantiate the subscriber object.
            Dim subscriber = New EasyUASubscriber()

            Console.WriteLine("Subscribing...")
            Dim fieldHandle = subscriber.SubscribeDataSetField(
                pubSubResolverDescriptor,
                pubSubConnectionDescriptor,
                filter,
                "Int32Fast",
                Sub(sender, eventArgs)
                    Console.WriteLine(eventArgs)
                End Sub)

            Console.WriteLine("Processing dataset message events for 20 seconds...")
            Threading.Thread.Sleep(20 * 1000)

            Console.WriteLine("Unsubscribing...")
            subscriber.UnsubscribeAllDataSets()

            Console.WriteLine("Waiting for 1 second...")
            ' Unsubscribe operation is asynchronous, messages may still come for a short while.
            Threading.Thread.Sleep(1 * 1000)

            Console.WriteLine("Finished...")
        End Sub
    End Class

    ' Example output
    '
    'Subscribing...
    'Processing dataset message events for 20 seconds...
    'Success
    'Success; 1626 {System.Int32}; Good
    'Success; 1711 {System.Int32}; Good
    'Success; 1741 {System.Int32}; Good
    'Success; 1837 {System.Int32}; Good
    'Success; 1897 {System.Int32}; Good
    'Success; 1993 {System.Int32}; Good
    'Success; 2082 {System.Int32}; Good
    'Success; 2135 {System.Int32}; Good
    'Success; 2185 {System.Int32}; Good
    'Success; 2241 {System.Int32}; Good
    'Success; 2324 {System.Int32}; Good
    'Success; 2368 {System.Int32}; Good
    'Success; 2423 {System.Int32}; Good
    'Success; 2445 {System.Int32}; Good
    'Success; 2497 {System.Int32}; Good
    'Success; 2584 {System.Int32}; Good
    'Success; 2608 {System.Int32}; Good
    '...

End Namespace
# This example shows how to subscribe to dataset messages on an OPC-UA PubSub connection, and then unsubscribe from that
# dataset.
#
# In order to produce network messages for this example, run the UADemoPublisher tool. For documentation, see
# https://kb.opclabs.com/UADemoPublisher_Basics . In some cases, you may have to specify the interface name to be used.
#
# Find all latest examples here: https://www.doc-that.com/files/onlinedocs/OPCLabs-ConnectivityStudio/Latest/examples.html .
# OPC client and subscriber examples in Python on GitHub: https://github.com/OPCLabs/Examples-ConnectivityStudio-Python .
# Missing some example? Ask us for it on our Online Forums, https://forum.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.BaseLib import *
from OpcLabs.EasyOpc.UA.PubSub import *
from OpcLabs.EasyOpc.UA.PubSub.OperationModel import *


# Define the PubSub resolver. We want the information be resolved from a PubSub binary configuration file that
# we have. The file itself is in this script's directory.
pubSubResolverDescriptor = UAPubSubResolverDescriptor.File(ResourceDescriptor('UADemoPublisher-Default.uabinary'))

# Define the PubSub connection we will work with, using its logical name in the PubSub configuration.
pubSubConnectionDescriptor = UAPubSubConnectionDescriptor()
pubSubConnectionDescriptor.Name = 'FixedLayoutConnection'
# In some cases you may have to set the interface (network adapter) name that needs to be used, similarly to
# the statement below. Your actual interface name may differ, of course.
#pubSubConnectionDescriptor.ResourceAddress.InterfaceName = 'Ethernet'

# Define the filter. The writer group and the dataset writer are specified using their logical names in the
# PubSub configuration. The publisher Id in the filter will be taken from the logical PubSub connection.
filter = UASubscribeDataSetFilter(
    UAWriterGroupDescriptor('FixedLayoutGroup'),
    UADataSetWriterDescriptor('SimpleWriter'))

# Instantiate the subscriber object.
subscriber = EasyUASubscriber()

print('Subscribing...')
fieldHandle = IEasyUASubscriberExtension.SubscribeDataSetField(subscriber,
    pubSubResolverDescriptor,
    pubSubConnectionDescriptor,
    filter,
    UADataSetFieldDescriptor('Int32Fast'),
    EasyUADataSetFieldMessageEventHandler(lambda sender, args: print(args)))

print('Processing dataset message events for 20 seconds...')
time.sleep(20)

print('Unsubscribing...')
IEasyUASubscriberExtension.UnsubscribeDataSetField(subscriber, fieldHandle)

print('Waiting for 1 second...')
# Unsubscribe operation is asynchronous, messages may still come for a short while.
time.sleep(1)

print('Finished.')
Inheritance Hierarchy

System.Object
   System.EventArgs
      OpcLabs.BaseLib.OperationModel.OperationEventArgs
         OpcLabs.EasyOpc.UA.PubSub.OperationModel.EasyUAPubSubMessageEventArgs
            OpcLabs.EasyOpc.UA.PubSub.OperationModel.EasyUADataSetFieldMessageEventArgs

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