QuickOPC User's Guide and Reference
Message Filtering (OPC UA PubSub)
Development Models > Imperative Programming Model > Imperative Programming Model for OPC UA PubSub > Subscribing to Information (OPC UA PubSub) > Message Filtering (OPC UA PubSub)
In This Topic

By message filtering in OPC UA PubSub, you specify which dataset message should be delivered to your application's code. Parameters that influence the message filtering are part of the dataset subscription descriptor (see Subscribing to Information (OPC UA PubSub)).

The various filtering parameters always have a default value that means "no filtering" (on the corresponding piece of message of data). By leaving them all at their defaults, you effectively specify "no filtering whatsoever". You can also set just some of these parameters to the values you are interested in, or you can set all of them.

You need to make a conscious choice about how broad or narrow your filtering will be. In most cases, it is best to define the filter as narrow as possible: Specify the precise publisher, writer group and/or dataset writer etc. that provides the dataset your are interested in. You can then write code (event or callback handlers) that already knows precisely which dataset is coming in, and interpret its contents reliably and easily. Sometimes, however, it makes sense to use a broader filter, and write an event or callback handler that deals with multiple incoming datasets in a generic way. The proper choice of the filter depends on the nature of your project.

For quick tests and experiments with OPC UA PubSub, and especially if you do not want to lose time coding when you need to figure out the proper settings, you can use the OpcCmd Utility - see Using OpcCmd Utility as OPC UA PubSub Subscriber. The utility allows to specify all parameters of the dataset subscriptions that are accessible from code, but simply by entering them on the command line. It also has a built-in support for displaying the incoming datasets and their fields.

Subscribe Dataset Filter

In its basic form, the subscribe dataset filter resides in the Filter Property of the UADataSetSubscriptionDescriptor Class, and the dataset subscription descriptor is part of the EasyUASubscribeDataSetArguments that are passed to the SubscribeDataSet Method. There are, however, several extension methods that allow you to make dataset subscription and specify the subscribe dataset filter in a different, easier way, depending on which parts you want to pass in.

Leaving any of the properties of the subscribe dataset filter at its default (initial) value means that no filtering is performed on that piece of information.

The most important parts of the subscribe dataset filter are below.  

You can also select whether you are interested in data, events, or both (the default), with the properties below.

It is also possibly to specify that you only want to receive dataset messages in which selected fields have certain value. To do, you set the required value under the key (that is a filed name or string form of a filed index) into the dictionary contained in the RequiredFieldValueDictionary Property. The component may, under some circumstances, you the mechanism of so-called promoted fields to achieve the filtering soon in the processing pipeline. This is, however, an implementation detail, and when specifying required field values, you do not have to be concerned about whether the field is promoted or not.

An additional filtering can be done based on the origin of the message. This is specified by the OriginPattern Property (a string). When not empty, is specifies a pattern (using the syntax of the Visual Basic LIKE operator) for the string form of the message origin. The origin type depends on the transport protocol, and is

Other Filters

Depending on the message and transport protocol mapping, there may be additional filtering applied to incoming PubSub messages.

For UADP message mapping, several parameters in UAUadpDataSetReaderMessageParameters Class (UadpDataSetReaderMessageParameters in CommunicationParameters Property of the dataset subscription descriptor) acts as filters as well. They are:

As with the properties on the subscribe dataset filter, leaving these properties at their default (initial) value denotes "no filtering" on that particular piece of information.

There is also, implicitly, a filtering mechanism based on security level of the PubSub message. The SecurityMode Property in the CommunicationParameters of the dataset subscription descriptor describes the minimum security mode of messages that you want to subscribe to. The default settings allows messages with any security mode through.

Data not in the message

You should not specify filtering on data that is not actually transferred in the PubSub messages. If you do, such messages will be filtered out, and you will not receive any useful data.

What does it actually mean? The OPC UA PubSub specification is very flexible, and it allows various pieces of information associated with the message be included or excluded. This may be because such piece of information is not relevant for the task at hand, and/or because (especially in UADP message mapping which is meant to be very terse) for efficiency reasons, the designer of the systems want to eliminate every unnecessary byte to be transferred.

Which information pieces are included or excluded is usually controlled by various flags in the publisher configuration. Some of them (such as optional timestamps) do not relate to filtering. But for those that appear in the filter, you must follow the rules below:

A typical example: You may have access to the publisher configuration, and you will see the concrete, non-zero dataset writer Id of the dataset you are interested in. If the publisher uses the UADP fixed layout (a commonly used profile), the dataset writer id, even though it appears in the publisher's configuration, is not transmitted in the PubSub messages ("on the wire"). Its purpose is served by knowing a concrete data offset (in the message) where the corresponding data starts. In this case, you should not put the dataset writer Id into the subscribe dataset filter.

If you are using OPC UA PubSub logical resolution, QuickOPC obtains the information about information included and excluded from the PubSub configuration (the various flags in the publisher configuration). Based on the publisher's configuration, the logical resolution process automatically leaves out the information not included in the PubSub messages from the filters. You therefore need not to do anything special on your side in this case.

Examples

The example below uses a filter that limits the dataset messages received to messages coming from a specific publisher Id, and for a specific dataset writer Id.

.NET

// This example shows how to subscribe to dataset messages and specify a filter, on an OPC-UA PubSub connection with
// UDP UADP mapping.
//
// In order to produce network messages for this example, run the UADemoPublisher tool. For documentation, see
// http://kb.opclabs.com/UADemoPublisher_Basics . In some cases, you may have to specify the interface name to be used.

using System;
using System.Collections.Generic;
using System.Threading;
using OpcLabs.EasyOpc.UA.PubSub;
using OpcLabs.EasyOpc.UA.PubSub.OperationModel;

namespace UADocExamples.PubSub._EasyUASubscriber
{
    partial class SubscribeDataSet
    {
        public static void Filter()
        {
            // Define the PubSub connection we will work with. Uses implicit conversion from a string.
            UAPubSubConnectionDescriptor pubSubConnectionDescriptor = "opc.udp://239.0.0.1";
            // 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. Publisher Id (unsigned 64-bits) is 31, and the dataset writer Id is 1.
            var filter = new UASubscribeDataSetFilter(
                UAPublisherId.CreateUInt64(31), 
                UAWriterGroupDescriptor.Null, 
                dataSetWriterDescriptor: 1);

            // Instantiate the subscriber object and hook events.
            var subscriber = new EasyUASubscriber();
            subscriber.DataSetMessage += subscriber_DataSetMessage_Filter;

            Console.WriteLine("Subscribing...");
            subscriber.SubscribeDataSet(pubSubConnectionDescriptor, filter);

            Console.WriteLine("Processing dataset message events for 20 seconds...");
            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.
            Thread.Sleep(1 * 1000);

            Console.WriteLine("Finished.");
        }

        static void subscriber_DataSetMessage_Filter(object sender, EasyUADataSetMessageEventArgs e)
        {
            // Display the dataset.
            if (e.Succeeded)
            {
                // An event with null DataSetData just indicates a successful connection.
                if (!(e.DataSetData is null))
                {
                    Console.WriteLine();
                    Console.WriteLine($"Dataset data: {e.DataSetData}");
                    foreach (KeyValuePair<string, UADataSetFieldData> pair in e.DataSetData.FieldDataDictionary)
                        Console.WriteLine(pair);
                }
            }
            else
            {
                Console.WriteLine();
                Console.WriteLine($"*** Failure: {e.ErrorMessageBrief}");
            }
        }

        // Example output:
        //
        //Subscribing...
        //Processing dataset message events for 20 seconds...
        //
        //Dataset data: Good; Data; publisher=(UInt64)31, writer=1, fields: 4
        //[#0, True {System.Boolean}; Good]
        //[#1, 7134 {System.Int32}; Good]
        //[#2, 7364 {System.Int32}; Good]
        //[#3, 10/1/2019 10:42:16 AM {System.DateTime}; Good]
        //
        //Dataset data: Good; Data; publisher=(UInt64)31, writer=1, fields: 4
        //[#1, 7135 {System.Int32}; Good]
        //[#2, 7429 {System.Int32}; Good]
        //[#3, 10/1/2019 10:42:17 AM {System.DateTime}; Good]
        //[#0, True {System.Boolean}; Good]
        //
        //Dataset data: Good; Data; publisher=(UInt64)31, writer=1, fields: 4
        //[#2, 7495 {System.Int32}; Good]
        //[#3, 10/1/2019 10:42:17 AM {System.DateTime}; Good]
        //[#0, True {System.Boolean}; Good]
        //[#1, 7135 {System.Int32}; Good]
        //
        //Dataset data: Good; Data; publisher=(UInt64)31, writer=1, fields: 4
        //[#1, 7136 {System.Int32}; Good]
        //[#2, 7560 {System.Int32}; Good]
        //[#3, 10/1/2019 10:42:18 AM {System.DateTime}; Good]
        //[#0, True {System.Boolean}; Good]
        //
        //Dataset data: Good; Data; publisher=(UInt64)31, writer=1, fields: 4
        //[#2, 7626 {System.Int32}; Good]
        //[#3, 10/1/2019 10:42:18 AM {System.DateTime}; Good]
        //[#0, True {System.Boolean}; Good]
        //[#1, 7136 {System.Int32}; Good]
        //
        //...
    }
}

# This example shows how to subscribe to dataset messages and specify a filter, on an OPC-UA PubSub connection with
# UDP UADP mapping.
#
# In order to produce network messages for this example, run the UADemoPublisher tool. For documentation, see
# http://kb.opclabs.com/UADemoPublisher_Basics . In some cases, you may have to specify the interface name to be used.

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

# Import .NET namespaces.
from System import *
from OpcLabs.EasyOpc.UA.PubSub import *
from OpcLabs.EasyOpc.UA.PubSub.Configuration import *
from OpcLabs.EasyOpc.UA.PubSub.OperationModel import *


def dataSetMessage(sender, e):
    # Display the dataset.
    if e.Succeeded:
        # An event with null DataSetData just indicates a successful connection.
        if e.DataSetData is not None:
            print('')
            print('Dataset data: ', e.DataSetData, sep='')
            for pair in e.DataSetData.FieldDataDictionary:
                print(pair)
    else:
        print('')
        print('*** Failure: ', e.ErrorMessageBrief, sep='')


# Define the PubSub connection we will work with. Uses implicit conversion from a string.
pubSubConnectionDescriptor = UAPubSubConnectionDescriptor.op_Implicit('opc.udp://239.0.0.1')
# 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. Publisher Id (unsigned 64-bits) is 31, and the dataset writer Id is 1.
filter = UASubscribeDataSetFilter(UAPublisherId.CreateUInt64(Decimal(31)),
                                  UAWriterGroupDescriptor.Null,
                                  UADataSetWriterDescriptor(1)) # dataSetWriterDescriptor

# Instantiate the subscriber object and hook events.
subscriber = EasyUASubscriber()
subscriber.DataSetMessage += dataSetMessage

print('Subscribing...')
IEasyUASubscriberExtension.SubscribeDataSet(subscriber, pubSubConnectionDescriptor, filter)

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

print('Unsubscribing...')
subscriber.UnsubscribeAllDataSets()

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

subscriber.DataSetMessage -= dataSetMessage

print('Finished.')

' This example shows how to subscribe to dataset messages and specify a filter, on an OPC-UA PubSub connection with
' UDP UADP mapping.
'
' In order to produce network messages for this example, run the UADemoPublisher tool. For documentation, see
' http://kb.opclabs.com/UADemoPublisher_Basics . In some cases, you may have to specify the interface name to be used.

Imports OpcLabs.EasyOpc.UA.PubSub
Imports OpcLabs.EasyOpc.UA.PubSub.OperationModel

Namespace PubSub._EasyUASubscriber
    Partial Friend Class SubscribeDataSet
        Public Shared Sub Filter()

            ' Define the PubSub connection we will work with. Uses implicit conversion from a string.
            Dim pubSubConnectionDescriptor As UAPubSubConnectionDescriptor = "opc.udp://239.0.0.1"
            ' 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. Publisher Id (unsigned 64-bits) Is 31, And the dataset writer Id Is 1.
            Dim filter = New UASubscribeDataSetFilter(UAPublisherId.CreateUInt64(31), UAWriterGroupDescriptor.Null, 1)

            ' Instantiate the subscriber object and hook events.
            Dim subscriber = New EasyUASubscriber()
            AddHandler subscriber.DataSetMessage, AddressOf subscriber_DataSetMessage_Filter

            Console.WriteLine("Subscribing...")
            subscriber.SubscribeDataSet(pubSubConnectionDescriptor, filter)

            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

        Private Shared Sub subscriber_DataSetMessage_Filter(ByVal sender As Object, ByVal e As EasyUADataSetMessageEventArgs)
            ' Display the dataset.
            If e.Succeeded Then
                ' An event with null DataSetData just indicates a successful connection.
                If e.DataSetData IsNot Nothing Then
                    Console.WriteLine()
                    Console.WriteLine($"Dataset data: {e.DataSetData}")
                    For Each pair As KeyValuePair(Of String, UADataSetFieldData) In e.DataSetData.FieldDataDictionary
                        Console.WriteLine(pair)
                    Next
                End If
            Else
                Console.WriteLine()
                Console.WriteLine($"*** Failure: {e.ErrorMessageBrief}")
            End If
        End Sub
    End Class

    ' Example output
    '
    'Subscribing...
    'Processing dataset message events for 20 seconds...
    '
    'Dataset data: Good; Data; publisher=(UInt64)31, writer=1, fields: 4
    '[#0, True {System.Boolean}; Good]
    '[#1, 7134 {System.Int32}; Good]
    '[#2, 7364 {System.Int32}; Good]
    '[#3, 10/1/2019 10:42:16 AM {System.DateTime}; Good]
    '
    'Dataset data: Good; Data; publisher=(UInt64)31, writer=1, fields: 4
    '[#1, 7135 {System.Int32}; Good]
    '[#2, 7429 {System.Int32}; Good]
    '[#3, 10/1/2019 10:42:17 AM {System.DateTime}; Good]
    '[#0, True {System.Boolean}; Good]
    '
    'Dataset data: Good; Data; publisher=(UInt64)31, writer=1, fields: 4
    '[#2, 7495 {System.Int32}; Good]
    '[#3, 10/1/2019 10:42:17 AM {System.DateTime}; Good]
    '[#0, True {System.Boolean}; Good]
    '[#1, 7135 {System.Int32}; Good]
    '
    'Dataset data: Good; Data; publisher=(UInt64)31, writer=1, fields: 4
    '[#1, 7136 {System.Int32}; Good]
    '[#2, 7560 {System.Int32}; Good]
    '[#3, 10/1/2019 10:42:18 AM {System.DateTime}; Good]
    '[#0, True {System.Boolean}; Good]
    '
    'Dataset data: Good; Data; publisher=(UInt64)31, writer=1, fields: 4
    '[#2, 7626 {System.Int32}; Good]
    '[#3, 10/1/2019 10:42:18 AM {System.DateTime}; Good]
    '[#0, True {System.Boolean}; Good]
    '[#1, 7136 {System.Int32}; Good]
    '
    '...

End Namespace

COM

// This example shows how to subscribe to dataset messages and specify a filter, on an OPC-UA PubSub connection with
// UDP UADP mapping.
//
// In order to produce network messages for this example, run the UADemoPublisher tool. For documentation, see
// http://kb.opclabs.com/UADemoPublisher_Basics . In some cases, you may have to specify the interface name to be used.

type
  TSubscriberEventHandlers76 = class
    procedure OnDataSetMessage(
      ASender: TObject;
      sender: OleVariant;
      const eventArgs: _EasyUADataSetMessageEventArgs);
  end;

class procedure SubscribeDataSet.Filter;
var
  ConnectionDescriptor: _UAPubSubConnectionDescriptor;
  SubscribeDataSetArguments: _EasyUASubscribeDataSetArguments;
  Subscriber: TEasyUASubscriber;
  SubscriberEventHandlers: TSubscriberEventHandlers76;
begin
  // Define the PubSub connection we will work with.
  SubscribeDataSetArguments := CoEasyUASubscribeDataSetArguments.Create;
  ConnectionDescriptor := SubscribeDataSetArguments.DataSetSubscriptionDescriptor.ConnectionDescriptor;
  ConnectionDescriptor.ResourceAddress.ResourceDescriptor.UrlString := 'opc.udp://239.0.0.1';
  // 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.
  //ConnectionDescriptor.ResourceAddress.InterfaceName := 'Ethernet';

  // Define the filter. Publisher Id (unsigned 64-bits) is 31, and the dataset writer Id is 1.
  SubscribeDataSetArguments.DataSetSubscriptionDescriptor.Filter.PublisherId.SetIdentifier(UAPublisherIdType_UInt64, 31);
  SubscribeDataSetArguments.DataSetSubscriptionDescriptor.Filter.DataSetWriterDescriptor.DataSetWriterId := 1;

  // Instantiate the subscriber object and hook events.
  Subscriber := TEasyUASubscriber.Create(nil);
  SubscriberEventHandlers := TSubscriberEventHandlers76.Create;
  Subscriber.OnDataSetMessage := SubscriberEventHandlers.OnDataSetMessage;

  WriteLn('Subscribing...');
  Subscriber.SubscribeDataSet(SubscribeDataSetArguments);

  WriteLn('Processing dataset message for 20 seconds...');
  PumpSleep(20*1000);

  WriteLn('Unsubscribing...');
  Subscriber.UnsubscribeAllDataSets;

  WriteLn('Waiting for 1 second...');
  // Unsubscribe operation is asynchronous, messages may still come for a short while.
  PumpSleep(1*1000);

  WriteLn('Finished.');
  FreeAndNil(Subscriber);
  FreeAndNil(SubscriberEventHandlers);
end;

procedure TSubscriberEventHandlers76.OnDataSetMessage(
  ASender: TObject;
  sender: OleVariant;
  const eventArgs: _EasyUADataSetMessageEventArgs);
var
  Count: Cardinal;
  DictionaryEntry2: _DictionaryEntry2;
  Element: OleVariant;
  FieldDataDictionaryEnumerator: IEnumVariant;
begin
  // Display the dataset.
  if eventArgs.Succeeded then
  begin
    // An event with null DataSetData just indicates a successful connection.
    if eventArgs.DataSetData <> nil then
    begin
      WriteLn;
      WriteLn('Dataset data: ', eventArgs.DataSetData.ToString);
      FieldDataDictionaryEnumerator := eventArgs.DataSetData.FieldDataDictionary.GetEnumerator;
      while (FieldDataDictionaryEnumerator.Next(1, Element, Count) = S_OK) do
      begin
        DictionaryEntry2 := IUnknown(Element) as _DictionaryEntry2;
        WriteLn(DictionaryEntry2.ToString);
      end;
    end;
  end
  else begin
    WriteLn;
      WriteLn('*** Failure: ', eventArgs.ErrorMessageBrief);
  end;
end;

// Example output:
//
//Subscribing...
//Processing dataset message events for 20 seconds...
//
//Dataset data: Good; Data; publisher=(UInt64)31, writer=1, fields: 4
//[BoolToggle, True {System.Boolean}; Good]
//[Int32, 25 {System.Int32}; Good]
//[Int32Fast, 928 {System.Int32}; Good]
//[DateTime, 10/3/2019 10:43:01 AM {System.DateTime}; Good]
//
//Dataset data: Good; Data; publisher=(UInt64)31, writer=1, fields: 4
//[Int32, 26 {System.Int32}; Good]
//[Int32Fast, 1007 {System.Int32}; Good]
//[DateTime, 10/3/2019 10:43:02 AM {System.DateTime}; Good]
//[BoolToggle, True {System.Boolean}; Good]
//
//Dataset data: Good; Data; publisher=(UInt64)31, writer=1, fields: 4
//[Int32Fast, 1113 {System.Int32}; Good]
//[DateTime, 10/3/2019 10:43:02 AM {System.DateTime}; Good]
//[BoolToggle, True {System.Boolean}; Good]
//[Int32, 26 {System.Int32}; Good]
//
//Dataset data: Good; Data; publisher=(UInt64)31, writer=1, fields: 4
//[BoolToggle, False {System.Boolean}; Good]
//[Int32, 27 {System.Int32}; Good]
//[Int32Fast, 1201 {System.Int32}; Good]
//[DateTime, 10/3/2019 10:43:03 AM {System.DateTime}; Good]
//
//Dataset data: Good; Data; publisher=(UInt64)31, writer=1, fields: 4
//[Int32Fast, 1260 {System.Int32}; Good]
//[DateTime, 10/3/2019 10:43:03 AM {System.DateTime}; Good]
//[BoolToggle, False {System.Boolean}; Good]
//[Int32, 27 {System.Int32}; Good]
//
//...

Rem This example shows how to subscribe to dataset messages and specify a filter, on an OPC-UA PubSub connection with
Rem UDP UADP mapping.
Rem
Rem In order to produce network messages for this example, run the UADemoPublisher tool. For documentation, see
Rem http://kb.opclabs.com/UADemoPublisher_Basics . In some cases, you may have to specify the interface name to be used.

Option Explicit

Const UAPublisherIdType_UInt64 = 4

' Define the PubSub connection we will work with.
Dim SubscribeDataSetArguments: Set SubscribeDataSetArguments = CreateObject("OpcLabs.EasyOpc.UA.PubSub.OperationModel.EasyUASubscribeDataSetArguments")
Dim ConnectionDescriptor: Set ConnectionDescriptor = SubscribeDataSetArguments.DataSetSubscriptionDescriptor.ConnectionDescriptor
ConnectionDescriptor.ResourceAddress.ResourceDescriptor.UrlString = "opc.udp://239.0.0.1"
' 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.
' ConnectionDescriptor.ResourceAddress.InterfaceName = "Ethernet"

' Define the filter. Publisher Id (unsigned 64-bits) is 31, and the dataset writer Id is 1.
SubscribeDataSetArguments.DataSetSubscriptionDescriptor.Filter.PublisherId.SetIdentifier UAPublisherIdType_UInt64, 31
SubscribeDataSetArguments.DataSetSubscriptionDescriptor.Filter.DataSetWriterDescriptor.DataSetWriterId = 1

' Instantiate the subscriber object and hook events.
Dim Subscriber: Set Subscriber = CreateObject("OpcLabs.EasyOpc.UA.PubSub.EasyUASubscriber")
WScript.ConnectObject Subscriber, "Subscriber_"

WScript.Echo "Subscribing..."
Subscriber.SubscribeDataSet SubscribeDataSetArguments

WScript.Echo "Processing dataset message events for 20 seconds..."
WScript.Sleep 20*1000

WScript.Echo "Unsubscribing..."
Subscriber.UnsubscribeAllDataSets

WScript.Echo "Waiting for 1 second..."
' Unsubscribe operation is asynchronous, messages may still come for a short while.
WScript.Sleep 1*1000

WScript.Echo "Finished."



Sub Subscriber_DataSetMessage(Sender, e)
    ' Display the dataset.
    If e.Succeeded Then
        ' An event with null DataSetData just indicates a successful connection.
        If Not (e.DataSetData Is Nothing) Then
            WScript.Echo
            WScript.Echo "Dataset data: " & e.DataSetData
            Dim Pair: For Each Pair in e.DataSetData.FieldDataDictionary
                WScript.Echo Pair
            Next
        End If
    Else
        WScript.Echo
        WScript.Echo "*** Failure: " & e.ErrorMessageBrief
    End If
End Sub



' Example output:
'
'Subscribing...
'Processing dataset message events for 20 seconds...
'
'Dataset data: Good; Data; publisher=(UInt64)31, writer=1, fields: 4
'[#0, True {System.Boolean}; Good]
'[#1, 7134 {System.Int32}; Good]
'[#2, 7364 {System.Int32}; Good]
'[#3, 10/1/2019 10:42:16 AM {System.DateTime}; Good]
'
'Dataset data: Good; Data; publisher=(UInt64)31, writer=1, fields: 4
'[#1, 7135 {System.Int32}; Good]
'[#2, 7429 {System.Int32}; Good]
'[#3, 10/1/2019 10:42:17 AM {System.DateTime}; Good]
'[#0, True {System.Boolean}; Good]
'
'Dataset data: Good; Data; publisher=(UInt64)31, writer=1, fields: 4
'[#2, 7495 {System.Int32}; Good]
'[#3, 10/1/2019 10:42:17 AM {System.DateTime}; Good]
'[#0, True {System.Boolean}; Good]
'[#1, 7135 {System.Int32}; Good]
'
'Dataset data: Good; Data; publisher=(UInt64)31, writer=1, fields: 4
'[#1, 7136 {System.Int32}; Good]
'[#2, 7560 {System.Int32}; Good]
'[#3, 10/1/2019 10:42:18 AM {System.DateTime}; Good]
'[#0, True {System.Boolean}; Good]
'
'Dataset data: Good; Data; publisher=(UInt64)31, writer=1, fields: 4
'[#2, 7626 {System.Int32}; Good]
'[#3, 10/1/2019 10:42:18 AM {System.DateTime}; Good]
'[#0, True {System.Boolean}; Good]
'[#1, 7136 {System.Int32}; Good]
'
'...


Rem This example shows how to subscribe to dataset messages and specify a filter, on an OPC-UA PubSub connection with
Rem UDP UADP mapping.
Rem
Rem In order to produce network messages for this example, run the UADemoPublisher tool. For documentation, see
Rem http://kb.opclabs.com/UADemoPublisher_Basics . In some cases, you may have to specify the interface name to be used.

' The subscriber object, with events
'Public WithEvents Subscriber1 As EasyUASubscriber

Private Sub EasyUASubscriber_SubscribeDataSet_Filter_Command_Click()
    OutputText = ""
    
    ' Define the PubSub connection we will work with.
    Dim subscribeDataSetArguments As New EasyUASubscribeDataSetArguments
    Dim ConnectionDescriptor As UAPubSubConnectionDescriptor
    Set ConnectionDescriptor = subscribeDataSetArguments.dataSetSubscriptionDescriptor.ConnectionDescriptor
    ConnectionDescriptor.ResourceAddress.ResourceDescriptor.UrlString = "opc.udp://239.0.0.1"
    ' 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.
    'ConnectionDescriptor.ResourceAddress.InterfaceName := 'Ethernet';

    ' Define the filter. Publisher Id (unsigned 64-bits) is 31, and the dataset writer Id is 1.
    Call subscribeDataSetArguments.dataSetSubscriptionDescriptor.Filter.PublisherId.SetIdentifier(UAPublisherIdType_UInt64, 31)
    subscribeDataSetArguments.dataSetSubscriptionDescriptor.Filter.DataSetWriterDescriptor.DataSetWriterId = 1
    
    ' Instantiate the subscriber object and hook events.
    Set Subscriber1 = New EasyUASubscriber
    
    OutputText = OutputText & "Subscribing..." & vbCrLf
    Call Subscriber1.SubscribeDataSet(subscribeDataSetArguments)

    OutputText = OutputText & "Processing dataset message for 20 seconds..." & vbCrLf
    Pause 20000

    OutputText = OutputText & "Unsubscribing..." & vbCrLf
    Subscriber1.UnsubscribeAllDataSets

    OutputText = OutputText & "Waiting for 1 second..." & vbCrLf
    ' Unsubscribe operation is asynchronous, messages may still come for a short while.
    Pause 1000

    Set Subscriber1 = Nothing

    OutputText = OutputText & "Finished." & vbCrLf
End Sub

Private Sub Subscriber1_OnDataSetMessage(ByVal sender As Variant, ByVal eventArgs As EasyUADataSetMessageEventArgs)
    ' Display the dataset
    If eventArgs.Succeeded Then
        ' An event with null DataSetData just indicates a successful connection.
        If Not eventArgs.DataSetData Is Nothing Then
            OutputText = OutputText & vbCrLf
            OutputText = OutputText & "Dataset data: " & eventArgs.DataSetData & vbCrLf
            Dim dictionaryEntry2: For Each dictionaryEntry2 In eventArgs.DataSetData.FieldDataDictionary
                OutputText = OutputText & dictionaryEntry2 & vbCrLf
            Next
        End If
    Else
        OutputText = OutputText & vbCrLf
        OutputText = OutputText & eventArgs.ErrorMessageBrief & vbCrLf
    End If
End Sub
' Example output:
'
'Subscribing...
'Processing dataset message events for 20 seconds...
'
'Dataset data: Good; Data; publisher=(UInt64)31, writer=1, fields: 4
'[BoolToggle, True {System.Boolean}; Good]
'[Int32, 25 {System.Int32}; Good]
'[Int32Fast, 928 {System.Int32}; Good]
'[DateTime, 10/3/2019 10:43:01 AM {System.DateTime}; Good]
'
'Dataset data: Good; Data; publisher=(UInt64)31, writer=1, fields: 4
'[Int32, 26 {System.Int32}; Good]
'[Int32Fast, 1007 {System.Int32}; Good]
'[DateTime, 10/3/2019 10:43:02 AM {System.DateTime}; Good]
'[BoolToggle, True {System.Boolean}; Good]
'
'Dataset data: Good; Data; publisher=(UInt64)31, writer=1, fields: 4
'[Int32Fast, 1113 {System.Int32}; Good]
'[DateTime, 10/3/2019 10:43:02 AM {System.DateTime}; Good]
'[BoolToggle, True {System.Boolean}; Good]
'[Int32, 26 {System.Int32}; Good]
'
'Dataset data: Good; Data; publisher=(UInt64)31, writer=1, fields: 4
'[BoolToggle, False {System.Boolean}; Good]
'[Int32, 27 {System.Int32}; Good]
'[Int32Fast, 1201 {System.Int32}; Good]
'[DateTime, 10/3/2019 10:43:03 AM {System.DateTime}; Good]
'
'Dataset data: Good; Data; publisher=(UInt64)31, writer=1, fields: 4
'[Int32Fast, 1260 {System.Int32}; Good]
'[DateTime, 10/3/2019 10:43:03 AM {System.DateTime}; Good]
'[BoolToggle, False {System.Boolean}; Good]
'[Int32, 27 {System.Int32}; Good]
'
'...

 

The filter in the example below only limits the messages received to those coming from a specific publisher Id.

.NET

// This example shows how to subscribe to all dataset messages with specific publisher Id, on an OPC-UA PubSub connection
// with UDP UADP mapping.
//
// In order to produce network messages for this example, run the UADemoPublisher tool. For documentation, see
// http://kb.opclabs.com/UADemoPublisher_Basics . In some cases, you may have to specify the interface name to be used.

using System;
using System.Collections.Generic;
using System.Threading;
using OpcLabs.EasyOpc.UA.PubSub;
using OpcLabs.EasyOpc.UA.PubSub.OperationModel;

namespace UADocExamples.PubSub._EasyUASubscriber
{
    partial class SubscribeDataSet
    {
        public static void PublisherId()
        {
            // Define the PubSub connection we will work with. Uses implicit conversion from a string.
            UAPubSubConnectionDescriptor pubSubConnectionDescriptor = "opc.udp://239.0.0.1";
            // 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 arguments for subscribing to the dataset, where the filter is (unsigned 64-bit) publisher Id 31.
            var subscribeDataSetArguments = new UASubscribeDataSetArguments(
                pubSubConnectionDescriptor, UAPublisherId.CreateUInt64(31));

            // Instantiate the subscriber object and hook events.
            var subscriber = new EasyUASubscriber();
            subscriber.DataSetMessage += subscriber_DataSetMessage_PublisherId;

            Console.WriteLine("Subscribing...");
            subscriber.SubscribeDataSet(subscribeDataSetArguments);

            Console.WriteLine("Processing dataset message events for 20 seconds...");
            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.
            Thread.Sleep(1 * 1000);

            Console.WriteLine("Finished.");
        }

        static void subscriber_DataSetMessage_PublisherId(object sender, EasyUADataSetMessageEventArgs e)
        {
            // Display the dataset.
            if (e.Succeeded)
            {
                // An event with null DataSetData just indicates a successful connection.
                if (!(e.DataSetData is null))
                {
                    Console.WriteLine();
                    Console.WriteLine($"Dataset data: {e.DataSetData}");
                    foreach (KeyValuePair<string, UADataSetFieldData> pair in e.DataSetData.FieldDataDictionary)
                        Console.WriteLine(pair);
                }
            }
            else
            {
                Console.WriteLine();
                Console.WriteLine($"*** Failure: {e.ErrorMessageBrief}");
            }
        }

        // Example output:
        //
        //Subscribing...
        //Processing dataset message events for 20 seconds...
        //
        //Dataset data: Good; Event; publisher=(UInt64)31, writer=51, fields: 4
        //[#0, True {System.Boolean}; Good]
        //[#1, 1237 {System.Int32}; Good]
        //[#2, 2514 {System.Int32}; Good]
        //[#3, 10/1/2019 9:03:59 AM {System.DateTime}; Good]
        //
        //Dataset data: Good; Data; publisher=(UInt64)31, writer=1, fields: 4
        //[#0, False {System.Boolean}; Good]
        //[#1, 1239 {System.Int32}; Good]
        //[#2, 2703 {System.Int32}; Good]
        //[#3, 10/1/2019 9:04:01 AM {System.DateTime}; Good]
        //
        //Dataset data: Good; Data; publisher=(UInt64)31, writer=4, fields: 16
        //[#0, False {System.Boolean}; Good]
        //[#1, 215 {System.Byte}; Good]
        //[#2, 1239 {System.Int16}; Good]
        //[#3, 1239 {System.Int32}; Good]
        //[#4, 1239 {System.Int64}; Good]
        //[#5, 87 {System.Int16}; Good]
        //[#6, 1239 {System.Int32}; Good]
        //[#7, 1239 {System.Int64}; Good]
        //[#8, 1239 {System.Decimal}; Good]
        //[#9, 1239 {System.Single}; Good]
        //[#10, 1239 {System.Double}; Good]
        //[#11, Romeo {System.String}; Good]
        //[#12, [20] {175, 186, 248, 246, 215, ...} {System.Byte[]}; Good]
        //[#13, d4492ca8-35c8-4b98-8edf-6ffa5ca041ca {System.Guid}; Good]
        //[#14, 10/1/2019 9:04:01 AM {System.DateTime}; Good]
        //[#15, [10] {1239, 1240, 1241, 1242, 1243, ...} {System.Int64[]}; Good]
        //
        //Dataset data: Good; Data; publisher=(UInt64)31, writer=1, fields: 4
        //[#2, 2722 {System.Int32}; Good]
        //[#3, 10/1/2019 9:04:01 AM {System.DateTime}; Good]
        //[#0, False {System.Boolean}; Good]
        //[#1, 1239 {System.Int32}; Good]
        //
        //Dataset data: Good; Data; publisher=(UInt64)31, writer=3, fields: 100
        //[#0, 39 {System.Int64}; Good]
        //[#1, 139 {System.Int64}; Good]
        //[#2, 239 {System.Int64}; Good]
        //[#3, 339 {System.Int64}; Good]
        //[#4, 439 {System.Int64}; Good]
        //[#5, 539 {System.Int64}; Good]
        //[#6, 639 {System.Int64}; Good]
        //[#7, 739 {System.Int64}; Good]
        //[#8, 839 {System.Int64}; Good]
        //[#9, 939 {System.Int64}; Good]
        //[#10, 1039 {System.Int64}; Good]
        //...
    }
}

# This example shows how to subscribe to all dataset messages with specific publisher Id, on an OPC-UA PubSub connection
# with UDP UADP mapping.
#
# In order to produce network messages for this example, run the UADemoPublisher tool. For documentation, see
# http://kb.opclabs.com/UADemoPublisher_Basics . In some cases, you may have to specify the interface name to be used.

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

# Import .NET namespaces.
from System import *
from OpcLabs.EasyOpc.UA.PubSub import *
from OpcLabs.EasyOpc.UA.PubSub.Configuration import *
from OpcLabs.EasyOpc.UA.PubSub.OperationModel import *


def dataSetMessage(sender, e):
    # Display the dataset.
    if e.Succeeded:
        # An event with null DataSetData just indicates a successful connection.
        if e.DataSetData is not None:
            print('')
            print('Dataset data: ', e.DataSetData, sep='')
            for pair in e.DataSetData.FieldDataDictionary:
                print(pair)
    else:
        print('')
        print('*** Failure: ', e.ErrorMessageBrief, sep='')


# Define the PubSub connection we will work with. Uses implicit conversion from a string.
pubSubConnectionDescriptor = UAPubSubConnectionDescriptor.op_Implicit('opc.udp://239.0.0.1')
# 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 arguments for subscribing to the dataset, where the filter is (unsigned 64-bit) publisher Id 31.
subscribeDataSetArguments = UASubscribeDataSetArguments(
    pubSubConnectionDescriptor,
    UASubscribeDataSetFilter(UAPublisherId.CreateUInt64(Decimal(31))))

# Instantiate the subscriber object and hook events.
subscriber = EasyUASubscriber()
subscriber.DataSetMessage += dataSetMessage

print('Subscribing...')
IEasyUASubscriberExtension.SubscribeDataSet(subscriber, subscribeDataSetArguments)

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

print('Unsubscribing...')
subscriber.UnsubscribeAllDataSets()

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

subscriber.DataSetMessage -= dataSetMessage

print('Finished.')

' This example shows how to subscribe to all dataset messages with specific publisher Id, on an OPC-UA PubSub connection
' with UDP UADP mapping.
'
' In order to produce network messages for this example, run the UADemoPublisher tool. For documentation, see
' http://kb.opclabs.com/UADemoPublisher_Basics . In some cases, you may have to specify the interface name to be used.

Imports OpcLabs.EasyOpc.UA.PubSub
Imports OpcLabs.EasyOpc.UA.PubSub.OperationModel

Namespace PubSub._EasyUASubscriber
    Partial Friend Class SubscribeDataSet
        Public Shared Sub PublisherId()

            ' Define the PubSub connection we will work with. Uses implicit conversion from a string.
            Dim pubSubConnectionDescriptor As UAPubSubConnectionDescriptor = "opc.udp://239.0.0.1"
            ' 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 arguments for subscribing to the dataset, where the filter Is (unsigned 64-bit) publisher Id 31.
            Dim subscribeDataSetArguments = New UASubscribeDataSetArguments(
                pubSubConnectionDescriptor, UAPublisherId.CreateUInt64(31))

            ' Instantiate the subscriber object and hook events.
            Dim subscriber = New EasyUASubscriber()
            AddHandler subscriber.DataSetMessage, AddressOf subscriber_DataSetMessage_PublisherId

            Console.WriteLine("Subscribing...")
            subscriber.SubscribeDataSet(subscribeDataSetArguments)

            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

        Private Shared Sub subscriber_DataSetMessage_PublisherId(ByVal sender As Object, ByVal e As EasyUADataSetMessageEventArgs)
            ' Display the dataset.
            If e.Succeeded Then
                ' An event with null DataSetData just indicates a successful connection.
                If e.DataSetData IsNot Nothing Then
                    Console.WriteLine()
                    Console.WriteLine($"Dataset data: {e.DataSetData}")
                    For Each pair As KeyValuePair(Of String, UADataSetFieldData) In e.DataSetData.FieldDataDictionary
                        Console.WriteLine(pair)
                    Next
                End If
            Else
                Console.WriteLine()
                Console.WriteLine($"*** Failure: {e.ErrorMessageBrief}")
            End If
        End Sub
    End Class



    ' Example output
    '
    'Subscribing...
    'Processing dataset message events for 20 seconds...
    '
    'Dataset data: Good; Event; publisher=(UInt64)31, writer=51, fields: 4
    '[#0, True {System.Boolean}; Good]
    '[#1, 1237 {System.Int32}; Good]
    '[#2, 2514 {System.Int32}; Good]
    '[#3, 10/1/2019 9:03:59 AM {System.DateTime}; Good]
    '
    'Dataset data: Good; Data; publisher=(UInt64)31, writer=1, fields: 4
    '[#0, False {System.Boolean}; Good]
    '[#1, 1239 {System.Int32}; Good]
    '[#2, 2703 {System.Int32}; Good]
    '[#3, 10/1/2019 9:04:01 AM {System.DateTime}; Good]
    '
    'Dataset data: Good; Data; publisher=(UInt64)31, writer=4, fields: 16
    '[#0, False {System.Boolean}; Good]
    '[#1, 215 {System.Byte}; Good]
    '[#2, 1239 {System.Int16}; Good]
    '[#3, 1239 {System.Int32}; Good]
    '[#4, 1239 {System.Int64}; Good]
    '[#5, 87 {System.Int16}; Good]
    '[#6, 1239 {System.Int32}; Good]
    '[#7, 1239 {System.Int64}; Good]
    '[#8, 1239 {System.Decimal}; Good]
    '[#9, 1239 {System.Single}; Good]
    '[#10, 1239 {System.Double}; Good]
    '[#11, Romeo {System.String}; Good]
    '[#12, [20] {175, 186, 248, 246, 215, ...} {System.Byte[]}; Good]
    '[#13, d4492ca8-35c8-4b98-8edf-6ffa5ca041ca {System.Guid}; Good]
    '[#14, 10/1/2019 9:04:01 AM {System.DateTime}; Good]
    '[#15, [10] {1239, 1240, 1241, 1242, 1243, ...} {System.Int64[]}; Good]
    '
    'Dataset data: Good; Data; publisher=(UInt64)31, writer=1, fields: 4
    '[#2, 2722 {System.Int32}; Good]
    '[#3, 10/1/2019 9:04:01 AM {System.DateTime}; Good]
    '[#0, False {System.Boolean}; Good]
    '[#1, 1239 {System.Int32}; Good]
    '
    'Dataset data: Good; Data; publisher=(UInt64)31, writer=3, fields: 100
    '[#0, 39 {System.Int64}; Good]
    '[#1, 139 {System.Int64}; Good]
    '[#2, 239 {System.Int64}; Good]
    '[#3, 339 {System.Int64}; Good]
    '[#4, 439 {System.Int64}; Good]
    '[#5, 539 {System.Int64}; Good]
    '[#6, 639 {System.Int64}; Good]
    '[#7, 739 {System.Int64}; Good]
    '[#8, 839 {System.Int64}; Good]
    '[#9, 939 {System.Int64}; Good]
    '[#10, 1039 {System.Int64}; Good]
    '...

End Namespace

COM

// This example shows how to subscribe to all dataset messages with specific publisher Id, on an OPC-UA PubSub connection
// with UDP UADP mapping.
//
// In order to produce network messages for this example, run the UADemoPublisher tool. For documentation, see
// http://kb.opclabs.com/UADemoPublisher_Basics . In some cases, you may have to specify the interface name to be used.

type
  TSubscriberEventHandlers80 = class
    procedure OnDataSetMessage(
      ASender: TObject;
      sender: OleVariant;
      const eventArgs: _EasyUADataSetMessageEventArgs);
  end;

class procedure SubscribeDataSet.PublisherId;
var
  ConnectionDescriptor: _UAPubSubConnectionDescriptor;
  SubscribeDataSetArguments: _EasyUASubscribeDataSetArguments;
  Subscriber: TEasyUASubscriber;
  SubscriberEventHandlers: TSubscriberEventHandlers80;
begin
  // Define the PubSub connection we will work with.
  SubscribeDataSetArguments := CoEasyUASubscribeDataSetArguments.Create;
  ConnectionDescriptor := SubscribeDataSetArguments.DataSetSubscriptionDescriptor.ConnectionDescriptor;
  ConnectionDescriptor.ResourceAddress.ResourceDescriptor.UrlString := 'opc.udp://239.0.0.1';
  // 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.
  //ConnectionDescriptor.ResourceAddress.InterfaceName := 'Ethernet';

  // Define the arguments for subscribing to the dataset, where the filter is (unsigned 64-bit) publisher Id 31.
  SubscribeDataSetArguments.DataSetSubscriptionDescriptor.Filter.PublisherId.SetIdentifier(UAPublisherIdType_UInt64, 31);

  // Instantiate the subscriber object and hook events.
  Subscriber := TEasyUASubscriber.Create(nil);
  SubscriberEventHandlers := TSubscriberEventHandlers80.Create;
  Subscriber.OnDataSetMessage := SubscriberEventHandlers.OnDataSetMessage;

  WriteLn('Subscribing...');
  Subscriber.SubscribeDataSet(SubscribeDataSetArguments);

  WriteLn('Processing dataset message for 20 seconds...');
  PumpSleep(20*1000);

  WriteLn('Unsubscribing...');
  Subscriber.UnsubscribeAllDataSets;

  WriteLn('Waiting for 1 second...');
  // Unsubscribe operation is asynchronous, messages may still come for a short while.
  PumpSleep(1*1000);

  WriteLn('Finished.');
  FreeAndNil(Subscriber);
  FreeAndNil(SubscriberEventHandlers);
end;

procedure TSubscriberEventHandlers80.OnDataSetMessage(
  ASender: TObject;
  sender: OleVariant;
  const eventArgs: _EasyUADataSetMessageEventArgs);
var
  Count: Cardinal;
  DictionaryEntry2: _DictionaryEntry2;
  Element: OleVariant;
  FieldDataDictionaryEnumerator: IEnumVariant;
begin
  // Display the dataset.
  if eventArgs.Succeeded then
  begin
    // An event with null DataSetData just indicates a successful connection.
    if eventArgs.DataSetData <> nil then
    begin
      WriteLn;
      WriteLn('Dataset data: ', eventArgs.DataSetData.ToString);
      FieldDataDictionaryEnumerator := eventArgs.DataSetData.FieldDataDictionary.GetEnumerator;
      while (FieldDataDictionaryEnumerator.Next(1, Element, Count) = S_OK) do
      begin
        DictionaryEntry2 := IUnknown(Element) as _DictionaryEntry2;
        WriteLn(DictionaryEntry2.ToString);
      end;
    end;
  end
  else begin
    WriteLn;
      WriteLn('*** Failure: ', eventArgs.ErrorMessageBrief);
  end;
end;

// Example output:
//
//Subscribing...
//Processing dataset message events for 20 seconds...
//
//Dataset data: Good; Event; publisher=(UInt64)31, writer=51, fields: 4
//[#0, True {System.Boolean}; Good]
//[#1, 1237 {System.Int32}; Good]
//[#2, 2514 {System.Int32}; Good]
//[#3, 10/1/2019 9:03:59 AM {System.DateTime}; Good]
//
//Dataset data: Good; Data; publisher=(UInt64)31, writer=1, fields: 4
//[#0, False {System.Boolean}; Good]
//[#1, 1239 {System.Int32}; Good]
//[#2, 2703 {System.Int32}; Good]
//[#3, 10/1/2019 9:04:01 AM {System.DateTime}; Good]
//
//Dataset data: Good; Data; publisher=(UInt64)31, writer=4, fields: 16
//[#0, False {System.Boolean}; Good]
//[#1, 215 {System.Byte}; Good]
//[#2, 1239 {System.Int16}; Good]
//[#3, 1239 {System.Int32}; Good]
//[#4, 1239 {System.Int64}; Good]
//[#5, 87 {System.Int16}; Good]
//[#6, 1239 {System.Int32}; Good]
//[#7, 1239 {System.Int64}; Good]
//[#8, 1239 {System.Decimal}; Good]
//[#9, 1239 {System.Single}; Good]
//[#10, 1239 {System.Double}; Good]
//[#11, Romeo {System.String}; Good]
//[#12, [20] {175, 186, 248, 246, 215, ...} {System.Byte[]}; Good]
//[#13, d4492ca8-35c8-4b98-8edf-6ffa5ca041ca {System.Guid}; Good]
//[#14, 10/1/2019 9:04:01 AM {System.DateTime}; Good]
//[#15, [10] {1239, 1240, 1241, 1242, 1243, ...} {System.Int64[]}; Good]
//
//Dataset data: Good; Data; publisher=(UInt64)31, writer=1, fields: 4
//[#2, 2722 {System.Int32}; Good]
//[#3, 10/1/2019 9:04:01 AM {System.DateTime}; Good]
//[#0, False {System.Boolean}; Good]
//[#1, 1239 {System.Int32}; Good]
//
//Dataset data: Good; Data; publisher=(UInt64)31, writer=3, fields: 100
//[#0, 39 {System.Int64}; Good]
//[#1, 139 {System.Int64}; Good]
//[#2, 239 {System.Int64}; Good]
//[#3, 339 {System.Int64}; Good]
//[#4, 439 {System.Int64}; Good]
//[#5, 539 {System.Int64}; Good]
//[#6, 639 {System.Int64}; Good]
//[#7, 739 {System.Int64}; Good]
//[#8, 839 {System.Int64}; Good]
//[#9, 939 {System.Int64}; Good]
//[#10, 1039 {System.Int64}; Good]
//...

Rem This example shows how to subscribe to all dataset messages with specific publisher Id, on an OPC-UA PubSub connection
Rem with UDP UADP mapping.
Rem
Rem In order to produce network messages for this example, run the UADemoPublisher tool. For documentation, see
Rem http://kb.opclabs.com/UADemoPublisher_Basics . In some cases, you may have to specify the interface name to be used.

Option Explicit

Const UAPublisherIdType_UInt64 = 4

' Define the PubSub connection we will work with.
Dim SubscribeDataSetArguments: Set SubscribeDataSetArguments = CreateObject("OpcLabs.EasyOpc.UA.PubSub.OperationModel.EasyUASubscribeDataSetArguments")
Dim ConnectionDescriptor: Set ConnectionDescriptor = SubscribeDataSetArguments.DataSetSubscriptionDescriptor.ConnectionDescriptor
ConnectionDescriptor.ResourceAddress.ResourceDescriptor.UrlString = "opc.udp://239.0.0.1"
' 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.
' ConnectionDescriptor.ResourceAddress.InterfaceName = "Ethernet"

' Define the arguments for subscribing to the dataset, where the filter is (unsigned 64-bit) publisher Id 31.
SubscribeDataSetArguments.DataSetSubscriptionDescriptor.Filter.PublisherId.SetIdentifier UAPublisherIdType_UInt64, 31

' Instantiate the subscriber object and hook events.
Dim Subscriber: Set Subscriber = CreateObject("OpcLabs.EasyOpc.UA.PubSub.EasyUASubscriber")
WScript.ConnectObject Subscriber, "Subscriber_"

WScript.Echo "Subscribing..."
Subscriber.SubscribeDataSet SubscribeDataSetArguments

WScript.Echo "Processing dataset message events for 20 seconds..."
WScript.Sleep 20*1000

WScript.Echo "Unsubscribing..."
Subscriber.UnsubscribeAllDataSets

WScript.Echo "Waiting for 1 second..."
' Unsubscribe operation is asynchronous, messages may still come for a short while.
WScript.Sleep 1*1000

WScript.Echo "Finished."



Sub Subscriber_DataSetMessage(Sender, e)
    ' Display the dataset.
    If e.Succeeded Then
        ' An event with null DataSetData just indicates a successful connection.
        If Not (e.DataSetData Is Nothing) Then
            WScript.Echo
            WScript.Echo "Dataset data: " & e.DataSetData
            Dim Pair: For Each Pair in e.DataSetData.FieldDataDictionary
                WScript.Echo Pair
            Next
        End If
    Else
        WScript.Echo
        WScript.Echo "*** Failure: " & e.ErrorMessageBrief
    End If
End Sub



' Example output:
'
'Subscribing...
'Processing dataset message events for 20 seconds...
'
'Dataset data: Good; Event; publisher=(UInt64)31, writer=51, fields: 4
'[#0, True {System.Boolean}; Good]
'[#1, 1237 {System.Int32}; Good]
'[#2, 2514 {System.Int32}; Good]
'[#3, 10/1/2019 9:03:59 AM {System.DateTime}; Good]
'
'Dataset data: Good; Data; publisher=(UInt64)31, writer=1, fields: 4
'[#0, False {System.Boolean}; Good]
'[#1, 1239 {System.Int32}; Good]
'[#2, 2703 {System.Int32}; Good]
'[#3, 10/1/2019 9:04:01 AM {System.DateTime}; Good]
'
'Dataset data: Good; Data; publisher=(UInt64)31, writer=4, fields: 16
'[#0, False {System.Boolean}; Good]
'[#1, 215 {System.Byte}; Good]
'[#2, 1239 {System.Int16}; Good]
'[#3, 1239 {System.Int32}; Good]
'[#4, 1239 {System.Int64}; Good]
'[#5, 87 {System.Int16}; Good]
'[#6, 1239 {System.Int32}; Good]
'[#7, 1239 {System.Int64}; Good]
'[#8, 1239 {System.Decimal}; Good]
'[#9, 1239 {System.Single}; Good]
'[#10, 1239 {System.Double}; Good]
'[#11, Romeo {System.String}; Good]
'[#12, [20] {175, 186, 248, 246, 215, ...} {System.Byte[]}; Good]
'[#13, d4492ca8-35c8-4b98-8edf-6ffa5ca041ca {System.Guid}; Good]
'[#14, 10/1/2019 9:04:01 AM {System.DateTime}; Good]
'[#15, [10] {1239, 1240, 1241, 1242, 1243, ...} {System.Int64[]}; Good]
'
'Dataset data: Good; Data; publisher=(UInt64)31, writer=1, fields: 4
'[#2, 2722 {System.Int32}; Good]
'[#3, 10/1/2019 9:04:01 AM {System.DateTime}; Good]
'[#0, False {System.Boolean}; Good]
'[#1, 1239 {System.Int32}; Good]
'
'Dataset data: Good; Data; publisher=(UInt64)31, writer=3, fields: 100
'[#0, 39 {System.Int64}; Good]
'[#1, 139 {System.Int64}; Good]
'[#2, 239 {System.Int64}; Good]
'[#3, 339 {System.Int64}; Good]
'[#4, 439 {System.Int64}; Good]
'[#5, 539 {System.Int64}; Good]
'[#6, 639 {System.Int64}; Good]
'[#7, 739 {System.Int64}; Good]
'[#8, 839 {System.Int64}; Good]
'[#9, 939 {System.Int64}; Good]
'[#10, 1039 {System.Int64}; Good]
'...


Rem This example shows how to subscribe to all dataset messages with specific publisher Id, on an OPC-UA PubSub connection
Rem with UDP UADP mapping.
Rem
Rem In order to produce network messages for this example, run the UADemoPublisher tool. For documentation, see
Rem http://kb.opclabs.com/UADemoPublisher_Basics . In some cases, you may have to specify the interface name to be used.

' The subscriber object, with events
'Public WithEvents Subscriber5 As EasyUASubscriber

Private Sub EasyUASubscriber_SubscribeDataSet_PublisherId_Command_Click()
    OutputText = ""
    ' Define the PubSub connection we will work with.
    Dim subscribeDataSetArguments As New EasyUASubscribeDataSetArguments
    Dim ConnectionDescriptor As UAPubSubConnectionDescriptor
    Set ConnectionDescriptor = subscribeDataSetArguments.dataSetSubscriptionDescriptor.ConnectionDescriptor
    ConnectionDescriptor.ResourceAddress.ResourceDescriptor.UrlString = "opc.udp://239.0.0.1"
    ' 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.
    'ConnectionDescriptor.ResourceAddress.InterfaceName := 'Ethernet';

    ' Define the arguments for subscribing to the dataset, where the filter is (unsigned 64-bit) publisher Id 31.
    Call subscribeDataSetArguments.dataSetSubscriptionDescriptor.Filter.PublisherId.SetIdentifier(UAPublisherIdType_UInt64, 31)
    
    ' Instantiate the subscriber object and hook events.
    Set Subscriber5 = New EasyUASubscriber
    
    OutputText = OutputText & "Subscribing..." & vbCrLf
    Call Subscriber5.SubscribeDataSet(subscribeDataSetArguments)

    OutputText = OutputText & "Processing dataset message for 20 seconds..." & vbCrLf
    Pause 20000

    OutputText = OutputText & "Unsubscribing..." & vbCrLf
    Subscriber5.UnsubscribeAllDataSets

    OutputText = OutputText & "Waiting for 1 second..." & vbCrLf
    ' Unsubscribe operation is asynchronous, messages may still come for a short while.
    Pause 1000

    Set Subscriber5 = Nothing

    OutputText = OutputText & "Finished." & vbCrLf
End Sub

Private Sub Subscriber5_DataSetMessage(ByVal sender As Variant, ByVal eventArgs As EasyUADataSetMessageEventArgs)
    ' Display the dataset
    If eventArgs.Succeeded Then
        ' An event with null DataSetData just indicates a successful connection.
        If Not eventArgs.DataSetData Is Nothing Then
            OutputText = OutputText & vbCrLf
            OutputText = OutputText & "Dataset data: " & eventArgs.DataSetData & vbCrLf
            Dim dictionaryEntry2: For Each dictionaryEntry2 In eventArgs.DataSetData.FieldDataDictionary
                OutputText = OutputText & dictionaryEntry2 & vbCrLf
            Next
        End If
    Else
        OutputText = OutputText & vbCrLf
        OutputText = OutputText & "*** Failure: " & eventArgs.ErrorMessageBrief & vbCrLf
    End If
' Example output:
'
'Subscribing...
'Processing dataset message events for 20 seconds...
'
'Dataset data: Good; Event; publisher=(UInt64)31, writer=51, fields: 4
'[#0, True {System.Boolean}; Good]
'[#1, 1237 {System.Int32}; Good]
'[#2, 2514 {System.Int32}; Good]
'[#3, 10/1/2019 9:03:59 AM {System.DateTime}; Good]
'
'Dataset data: Good; Data; publisher=(UInt64)31, writer=1, fields: 4
'[#0, False {System.Boolean}; Good]
'[#1, 1239 {System.Int32}; Good]
'[#2, 2703 {System.Int32}; Good]
'[#3, 10/1/2019 9:04:01 AM {System.DateTime}; Good]
'
'Dataset data: Good; Data; publisher=(UInt64)31, writer=4, fields: 16
'[#0, False {System.Boolean}; Good]
'[#1, 215 {System.Byte}; Good]
'[#2, 1239 {System.Int16}; Good]
'[#3, 1239 {System.Int32}; Good]
'[#4, 1239 {System.Int64}; Good]
'[#5, 87 {System.Int16}; Good]
'[#6, 1239 {System.Int32}; Good]
'[#7, 1239 {System.Int64}; Good]
'[#8, 1239 {System.Decimal}; Good]
'[#9, 1239 {System.Single}; Good]
'[#10, 1239 {System.Double}; Good]
'[#11, Romeo {System.String}; Good]
'[#12, [20] {175, 186, 248, 246, 215, ...} {System.Byte[]}; Good]
'[#13, d4492ca8-35c8-4b98-8edf-6ffa5ca041ca {System.Guid}; Good]
'[#14, 10/1/2019 9:04:01 AM {System.DateTime}; Good]
'[#15, [10] {1239, 1240, 1241, 1242, 1243, ...} {System.Int64[]}; Good]
'
'Dataset data: Good; Data; publisher=(UInt64)31, writer=1, fields: 4
'[#2, 2722 {System.Int32}; Good]
'[#3, 10/1/2019 9:04:01 AM {System.DateTime}; Good]
'[#0, False {System.Boolean}; Good]
'[#1, 1239 {System.Int32}; Good]
'
'Dataset data: Good; Data; publisher=(UInt64)31, writer=3, fields: 100
'[#0, 39 {System.Int64}; Good]
'[#1, 139 {System.Int64}; Good]
'[#2, 239 {System.Int64}; Good]
'[#3, 339 {System.Int64}; Good]
'[#4, 439 {System.Int64}; Good]
'[#5, 539 {System.Int64}; Good]
'[#6, 639 {System.Int64}; Good]
'[#7, 739 {System.Int64}; Good]
'[#8, 839 {System.Int64}; Good]
'[#9, 939 {System.Int64}; Good]
'[#10, 1039 {System.Int64}; Good]
'...
End Sub

 

See Also
Subscribing to Information (OPC UA PubSub)
OPC UA PubSub logical resolution

Examples - OPC UA PubSub

Examples - OPC UA PubSub - Specify filter for dataset messages
Examples - OPC UA PubSub - Subscribe to dataset messages from specific publisher

Reference

UASubscribeDataSetFilter Class
UAUadpDataSetReaderMessageParameters Class

 

 

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