Implicit Type Conversion(UADataChangeFilter,Double) Operator

Converts a double to a data change filter, by creating a filter with absolute deadband.

Syntax

Visual Basic
C#
C++/CLI

'Declaration
 
<NotNullAttribute()>
Overloads Public Operator Widening CType( _
   ByVal absoluteDeadbandValue As Double _
) As UADataChangeFilter

'Usage

[NotNull()]
public UADataChangeFilter operator implicit( 
   double absoluteDeadbandValue
)

[NotNull()]
public:
operator UADataChangeFilter^ ( 
   double absoluteDeadbandValue
)

Parameters

absoluteDeadbandValue: A data change filter's absolute deadband value.

Return Value

Returns a data change filter specifying the given absolute deadband, and triggered by UADataChangeTrigger.StatusValueTimestamp.

Example

// This example shows how to subscribe to changes of a monitored item with absolute deadband.
//
// Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .

using System;
using OpcLabs.EasyOpc.UA;
using OpcLabs.EasyOpc.UA.OperationModel;

namespace UADocExamples._EasyUAClient
{
    partial class SubscribeDataChange
    {
        public static void AbsoluteDeadband()
        {
            UAEndpointDescriptor endpointDescriptor =
                "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer";
            // or "http://opcua.demo-this.com:51211/UA/SampleServer" (currently not supported)
            // or "https://opcua.demo-this.com:51212/UA/SampleServer/"

            // Instantiate the client object and hook events
            var client = new EasyUAClient();
            client.DataChangeNotification += client_DataChangeNotification_AbsoluteDeadband;

            const double absoluteDeadband = 50;
            Console.WriteLine($"Subscribing with absolute deadband {absoluteDeadband}...");
            // The UADataChangeFilter has an implicit conversion from Double, which creates a filter with the specified
            // absolute deadband.
            client.SubscribeDataChange(endpointDescriptor, 
                "nsu=http://test.org/UA/Data/ ;i=11194",    // /Data.Dynamic.AnalogScalar.Int32Value
                samplingInterval:1000, 
                dataChangeFilter: absoluteDeadband);

            Console.WriteLine("Processing data change events for 20 seconds...");
            System.Threading.Thread.Sleep(20 * 1000);

            Console.WriteLine("Unsubscribing...");
            client.UnsubscribeAllMonitoredItems();

            Console.WriteLine("Waiting for 5 seconds...");
            System.Threading.Thread.Sleep(5 * 1000);
        }

        static void client_DataChangeNotification_AbsoluteDeadband(object sender, EasyUADataChangeNotificationEventArgs e)
        {
            // Display value
            if (e.Succeeded)
                Console.WriteLine("Value: {0}", e.AttributeData.Value);
            else
                Console.WriteLine("*** Failure: {0}", e.ErrorMessageBrief);
        }
    }
}

# This example shows how to subscribe to changes of a monitored item with absolute deadband.
#
# 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 .
# The QuickOPC package is needed. Install it using "pip install opclabs_quickopc".
import opclabs_quickopc
import time

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


def dataChangeNotification(sender, e):
    # Display value.
    if e.Succeeded:
        print('Value: ', e.AttributeData.Value, sep='')
    else:
        print('*** Failure: ', e.ErrorMessageBrief, sep='')


endpointDescriptor = UAEndpointDescriptor('opc.tcp://opcua.demo-this.com:51210/UA/SampleServer')
# or 'http://opcua.demo-this.com:51211/UA/SampleServer' (currently not supported)
# or 'https://opcua.demo-this.com:51212/UA/SampleServer/'

# Instantiate the client object and hook events.
client = EasyUAClient()
client.DataChangeNotification += dataChangeNotification

ABSOLUTE_DEADBAND = 50
print('Subscribing with absolute deadband ', ABSOLUTE_DEADBAND, '...', sep='')
IEasyUAClientExtension.SubscribeDataChange(client,
    endpointDescriptor,
    UANodeDescriptor('nsu=http://test.org/UA/Data/ ;i=11194'),
    1000,   # samplingInterval
    UADataChangeFilter(ABSOLUTE_DEADBAND))

print('Processing data change events for 20 seconds...')
time.sleep(20)

print('Unsubscribing...')
client.UnsubscribeAllMonitoredItems()

print('Waiting for 5 seconds...')
time.sleep(5)

print('Finished.')

' This example shows how to subscribe to changes of a monitored item with absolute deadband.
'
' Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .

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

Namespace _EasyUAClient
    Partial Friend Class SubscribeDataChange
        Public Shared Sub AbsoluteDeadband()

            ' Define which server we will work with.
            Dim endpointDescriptor As UAEndpointDescriptor =
                    "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer"
            ' or "http://opcua.demo-this.com:51211/UA/SampleServer" (currently not supported)
            ' or "https://opcua.demo-this.com:51212/UA/SampleServer/"

            ' Instantiate the client object and hook events
            Dim client = New EasyUAClient()
            AddHandler client.DataChangeNotification, AddressOf client_DataChangeNotification_AbsoluteDeadband

            Const absoluteDeadband As Double = 50
            Console.WriteLine("Subscribing with absolute deadband {0}...", absoluteDeadband)
            ' The UADataChangeFilter has an implicit conversion from Double, which creates a filter with the specified
            ' absolute deadband.
            client.SubscribeDataChange(endpointDescriptor,
                "nsu=http://test.org/UA/Data/ ;i=11194",    ' /Data.Dynamic.AnalogScalar.Int32Value
                samplingInterval:=1000,
                dataChangeFilter:=absoluteDeadband)

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

            Console.WriteLine("Unsubscribing...")
            client.UnsubscribeAllMonitoredItems()

            Console.WriteLine("Waiting for 5 seconds...")
            Threading.Thread.Sleep(5 * 1000)
        End Sub

        Private Shared Sub client_DataChangeNotification_AbsoluteDeadband(ByVal sender As Object, ByVal e As EasyUADataChangeNotificationEventArgs)
            ' Display value
            If e.Succeeded Then
                Console.WriteLine("Value: {0}", e.AttributeData.Value)
            Else
                Console.WriteLine("*** Failure: {0}", e.ErrorMessageBrief)
            End If
        End Sub
    End Class
End Namespace

CSharp
Python
VB.NET

// This example shows how to subscribe to changes of multiple monitored items with absolute deadband.
//
// Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .

using System;
using OpcLabs.EasyOpc.UA;
using OpcLabs.EasyOpc.UA.OperationModel;

namespace UADocExamples._EasyUAClient
{
    partial class SubscribeMultipleMonitoredItems
    {
        public static void AbsoluteDeadband()
        {
            UAEndpointDescriptor endpointDescriptor =
                "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer";
            // or "http://opcua.demo-this.com:51211/UA/SampleServer" (currently not supported)
            // or "https://opcua.demo-this.com:51212/UA/SampleServer/"

            // Instantiate the client object and hook events
            var client = new EasyUAClient();
            client.DataChangeNotification += client_DataChangeNotification_AbsoluteDeadband;

            Console.WriteLine("Subscribing with different absolute deadbands...");
            // The UADataChangeFilter has an implicit conversion from Double, which creates a filter with the specified
            // absolute deadband.
            client.SubscribeMultipleMonitoredItems(new[]
                {
                    new EasyUAMonitoredItemArguments(null, endpointDescriptor,
                        "nsu=http://test.org/UA/Data/ ;i=11194",    // /Data.Dynamic.AnalogScalar.Int32Value
                        new UAMonitoringParameters(samplingInterval:100, dataChangeFilter:50)),
                    new EasyUAMonitoredItemArguments(null, endpointDescriptor,
                        "nsu=http://test.org/UA/Data/ ;i=11218",    // /Data.Dynamic.AnalogScalar.FloatValue
                        new UAMonitoringParameters(samplingInterval:100, dataChangeFilter:20))
                });

            Console.WriteLine("Processing monitored item changed events for 10 seconds...");
            System.Threading.Thread.Sleep(10 * 1000);

            Console.WriteLine("Unsubscribing...");
            client.UnsubscribeAllMonitoredItems();

            Console.WriteLine("Waiting for 5 seconds...");
            System.Threading.Thread.Sleep(5 * 1000);
        }

        static void client_DataChangeNotification_AbsoluteDeadband(object sender, EasyUADataChangeNotificationEventArgs e)
        {
            // Display value
            if (e.Succeeded)
                Console.WriteLine("{0}: {1}", e.Arguments.NodeDescriptor, e.AttributeData.Value);
            else
                Console.WriteLine("{0} *** Failure: {1}", e.Arguments.NodeDescriptor, e.ErrorMessageBrief);
        }
    }
}

# This example shows how to subscribe to changes of multiple monitored items with absolute deadband.
#
# 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 .
# The QuickOPC package is needed. Install it using "pip install opclabs_quickopc".
import opclabs_quickopc
import time

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


def dataChangeNotification(sender, e):
    # Display value.
    if e.Succeeded:
        print(e.Arguments.NodeDescriptor, ': ', e.AttributeData.Value, sep='')
    else:
        print(e.Arguments.NodeDescriptor, ' *** Failure: ', e.ErrorMessageBrief, sep='')


endpointDescriptor = UAEndpointDescriptor('opc.tcp://opcua.demo-this.com:51210/UA/SampleServer')
# or 'http://opcua.demo-this.com:51211/UA/SampleServer' (currently not supported)
# or 'https://opcua.demo-this.com:51212/UA/SampleServer/'

# Instantiate the client object and hook events.
client = EasyUAClient()
client.DataChangeNotification += dataChangeNotification

print('Subscribing with different absolute deadbands...')
client.SubscribeMultipleMonitoredItems([
    EasyUAMonitoredItemArguments(
        None,
        endpointDescriptor,
        UANodeDescriptor('nsu=http://test.org/UA/Data/ ;i=11194'),
        UAMonitoringParameters(100, UADataChangeFilter(50))),   # samplingInterval, dataChangeFilter
    EasyUAMonitoredItemArguments(
        None,
        endpointDescriptor,
        UANodeDescriptor('nsu=http://test.org/UA/Data/ ;i=11218'),
        UAMonitoringParameters(100, UADataChangeFilter(20))),   # samplingInterval, dataChangeFilter
    ])

print('Processing data change events for 10 seconds...')
time.sleep(10)

print('Unsubscribing...')
client.UnsubscribeAllMonitoredItems()

print('Waiting for 5 seconds...')
time.sleep(5)

print('Finished.')

' This example shows how to subscribe to changes of multiple monitored items with absolute deadband.
'
' Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .

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

Namespace _EasyUAClient
    Partial Friend Class SubscribeMultipleMonitoredItems
        Public Shared Sub AbsoluteDeadband()

            ' Define which server we will work with.
            Dim endpointDescriptor As UAEndpointDescriptor =
                    "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer"
            ' or "http://opcua.demo-this.com:51211/UA/SampleServer" (currently not supported)
            ' or "https://opcua.demo-this.com:51212/UA/SampleServer/"

            ' Instantiate the client object and hook events
            Dim client = New EasyUAClient()
            AddHandler client.DataChangeNotification, AddressOf client_DataChangeNotification_AbsoluteDeadband

            Console.WriteLine("Subscribing with different absolute deadbands...")
            ' The UADataChangeFilter has an implicit conversion from Double, which creates a filter with the specified
            ' absolute deadband.
            client.SubscribeMultipleMonitoredItems(New EasyUAMonitoredItemArguments() _
                {
                    New EasyUAMonitoredItemArguments(Nothing, endpointDescriptor,
                        "nsu=http://test.org/UA/Data/ ;i=11194",    ' /Data.Dynamic.AnalogScalar.Int32Value
                        New UAMonitoringParameters(samplingInterval:=100, dataChangeFilter:=50)),
                    New EasyUAMonitoredItemArguments(Nothing, endpointDescriptor,
                        "nsu=http://test.org/UA/Data/ ;i=11218",    ' /Data.Dynamic.AnalogScalar.FloatValue
                        New UAMonitoringParameters(samplingInterval:=100, dataChangeFilter:=20))
                }
             )

            Console.WriteLine("Processing monitored item changed events for 10 seconds...")
            Threading.Thread.Sleep(10 * 1000)

            Console.WriteLine("Unsubscribing...")
            client.UnsubscribeAllMonitoredItems()

            Console.WriteLine("Waiting for 5 seconds...")
            Threading.Thread.Sleep(5 * 1000)
        End Sub

        Private Shared Sub client_DataChangeNotification_AbsoluteDeadband(ByVal sender As Object, ByVal e As EasyUADataChangeNotificationEventArgs)
            ' Display value
            If e.Succeeded Then
                Console.WriteLine("{0}: {1}", e.Arguments.NodeDescriptor, e.AttributeData.Value)
            Else
                Console.WriteLine("{0} *** Failure: {1}", e.Arguments.NodeDescriptor, e.ErrorMessageBrief)
            End If
        End Sub
    End Class
End Namespace

CSharp

// Shows how to observe OPC UA data changes with a specified absolute deadband.
//
// Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .

using OpcLabs.EasyOpc.UA.Reactive;
using System;
using System.Threading;
using OpcLabs.EasyOpc.UA;
using OpcLabs.EasyOpc.UA.OperationModel;

namespace ReactiveDocExamples
{
    namespace _UADataChangeNotificationObservable
    {
        partial class Subscribe
        {
            public static void AbsoluteDeadband()
            {
                // Define which server we will work with.
                UAEndpointDescriptor endpointDescriptor =
                    "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer";
                // or "http://opcua.demo-this.com:51211/UA/SampleServer" (currently not supported)
                // or "https://opcua.demo-this.com:51212/UA/SampleServer/"

                const double absoluteDeadband = 50;
                Console.WriteLine($"Creating observable with absolute deadband {absoluteDeadband}...");
                var attributeArguments = new UAAttributeArguments(
                    endpointDescriptor,
                    "nsu=http://test.org/UA/Data/ ;i=11194");    // /Data.Dynamic.AnalogScalar.Int32Value
                var monitoredItemArguments = new UAMonitoredItemArguments(
                    attributeArguments,
                    new UAMonitoringParameters(samplingInterval: 1000, dataChangeFilter: absoluteDeadband));
                UADataChangeNotificationObservable<int> observable =
                    UADataChangeNotificationObservable.Create<int>(monitoredItemArguments);

                Console.WriteLine("Subscribing...");
                using (observable.Subscribe(e => Console.WriteLine(
                    (e.Exception is null) ? e.AttributeData.ToString() : e.Exception.GetBaseException().ToString())))
                {
                    Console.WriteLine("Waiting for 10 seconds...");
                    Thread.Sleep(10*1000);

                    Console.WriteLine("Unsubscribing...");
                }

                Console.WriteLine("Waiting for 2 seconds...");
                Thread.Sleep(2 * 1000);
            }
        }
    }
}

Requirements

Target Platforms: .NET Framework: Windows 10 (selected versions), Windows 11 (selected versions), Windows Server 2016, Windows Server 2022; .NET: Linux, macOS, Microsoft Windows

Reference

UADataChangeFilter Class
UADataChangeFilter Members
Overload List

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