Match Method (_UANodeDescriptor)

Determines whether the node descriptor matches another node descriptor.

Syntax

Visual Basic
C#
C++/CLI

'Declaration
 
Function Match( _
   ByVal other As Object _
) As Boolean

'Usage
 
Dim instance As _UANodeDescriptor
Dim other As Object
Dim value As Boolean
 
value = instance.Match(other)

bool Match( 
   object other
)

bool Match( 
   Object^ other
)

Parameters

other: A OpcLabs.EasyOpc.UA.UANodeDescriptor. The node descriptor to match against.

Return Value

Returns true if two node descriptors match; otherwise, returns false.

Exceptions

Exception Description

Exception	Description
System.ArgumentNullException	A `null` reference (`Nothing` in Visual Basic) is passed to a method that does not accept it as a valid argument. This is a usage error, i.e. it will never occur (the exception will not be thrown) in a correctly written program. Your code should not catch this exception.

System.ArgumentNullException

A null reference (Nothing in Visual Basic) is passed to a method that does not accept it as a valid argument.

This is a usage error, i.e. it will never occur (the exception will not be thrown) in a correctly written program. Your code should not catch this exception.

Remarks

Two node descriptors match if any information that is present in both node descriptors match. For example, if a node Id in one of the node descriptors is not present (null), a node Id in the other node descriptor can be anything, or also not present. But if a node Id is present in both node descriptors, they must match. Same rules apply to the browse path portion of the node descriptor.

Example

.NET

// Shows how to write complex data with OPC UA Complex Data plug-in.

using System;
using OpcLabs.BaseLib.DataTypeModel;
using OpcLabs.EasyOpc.UA;
using OpcLabs.EasyOpc.UA.ComplexData;
using OpcLabs.EasyOpc.UA.OperationModel;

namespace UADocExamples.ComplexData._EasyUAClient
{
    class WriteValue
    {
        public static void Main1()
        {
            // Define which server and node 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/"
            UANodeDescriptor nodeDescriptor =
                "nsu=http://test.org/UA/Data/ ;i=10239"; // [ObjectsFolder]/Data.Static.Scalar.StructureValue

            // Instantiate the client object.
            var client = new EasyUAClient();

            // Read a node which returns complex data. 
            // We know that this node returns complex data, so we can type cast to UAGenericObject.
            Console.WriteLine("Reading...");
            UAGenericObject genericObject;
            try
            {
                genericObject = (UAGenericObject)client.ReadValue(endpointDescriptor, nodeDescriptor);
            }
            catch (UAException uaException)
            {
                Console.WriteLine("*** Failure: {0}", uaException.GetBaseException().Message);
                return;
            }


            // Modify the data read.
            // This node returns one of the two data types, randomly (this is not common, usually the type is fixed). The
            // data types are sub-types of one common type which the data type of the node. We therefore use the data type 
            // ID in the returned UAGenericObject to detect which data type has been returned.

            // For processing the internals of the data, refer to examples for GenericData and DataType classes.
            // We know how the data is structured, and have hard-coded a logic that modifies certain values inside. It is
            // also possible to discover the structure of the data type in the program, and write generic clients that can 
            // cope with any kind of complex data.
            //
            // Note that the code below is not fully robust - it will throw an exception if the data is not as expected.
            Console.WriteLine("Modifying...");
            Console.WriteLine(genericObject.DataTypeId);
            if (genericObject.DataTypeId.NodeDescriptor.Match("nsu=http://test.org/UA/Data/ ;i=9440"))  // ScalarValueDataType
            {
                // Negate the byte in the "ByteValue" field.
                var structuredData = (StructuredData)genericObject.GenericData;
                var byteValue = (PrimitiveData)structuredData.FieldData["ByteValue"];
                byteValue.Value = (Byte)~((Byte)byteValue.Value);
                Console.WriteLine(byteValue.Value);
            }
            else if (genericObject.DataTypeId.NodeDescriptor.Match("nsu=http://test.org/UA/Data/ ;i=9669")) // ArrayValueDataType
            {
                // Negate bytes at indexes 0 and 1 of the array in the "ByteValue" field.
                var structuredData = (StructuredData)genericObject.GenericData;
                var byteValue = (SequenceData)structuredData.FieldData["ByteValue"];
                var element0 = (PrimitiveData)byteValue.Elements[0];
                var element1 = (PrimitiveData)byteValue.Elements[1];
                element0.Value = (Byte)~((Byte)element0.Value);
                element1.Value = (Byte)~((Byte)element1.Value);
                Console.WriteLine(element0.Value);
                Console.WriteLine(element1.Value);
            }


            // Write the modified complex data back to the node.
            // The data type ID in the UAGenericObject is borrowed without change from what we have read, so that the server
            // knows which data type we are writing. The data type ID not necessary if writing precisely the same data type
            // as the node has (not a subtype).
            Console.WriteLine("Writing...");
            try
            {
                client.WriteValue(endpointDescriptor, nodeDescriptor, genericObject);
            }
            catch (UAException uaException)
            {
                Console.WriteLine("*** Failure: {0}", uaException.GetBaseException().Message);
            }
        }
    }
}

# Shows how to write complex data with OPC UA Complex Data plug-in.

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

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


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/'

# [ObjectsFolder]/Data.Static.Scalar.StructureValue
nodeDescriptor = UANodeDescriptor('nsu=http://test.org/UA/Data/ ;i=10239')

# Instantiate the client object.
client = EasyUAClient()

# Read a node which returns complex data.
# We know that this node returns complex data, so we can type cast to UAGenericObject.
try:
    print('Reading...')
    genericObject = IEasyUAClientExtension.ReadValue(client, endpointDescriptor, nodeDescriptor)
except UAException as uaException:
    print('*** Failure: ' + uaException.GetBaseException().Message)
    exit()

# Modify the data read.
# This node returns one of the two data types, randomly (this is not common, usually the type is fixed). The
# data types are sub-types of one common type which the data type of the node. We therefore use the data type
# ID in the returned UAGenericObject to detect which data type has been returned.
#
# For processing the internals of the data, refer to examples for GenericData and DataType classes.
# We know how the data is structured, and have hard-coded a logic that modifies certain values inside. It is
# also possible to discover the structure of the data type in the program, and write generic clients that can
# cope with any kind of complex data.
#
# Note that the code below is not fully robust - it will throw an exception if the data is not as expected.
print ('Modifying...')
print(genericObject.DataTypeId)
if genericObject.DataTypeId.NodeDescriptor.Match(UANodeDescriptor('nsu=http://test.org/UA/Data/ ;i=9440')):  # ScalarValueDataType
    # Negate the byte in the "ByteValue" field.
    structuredData = genericObject.GenericData
    byteValue = structuredData.FieldData.get_Item('ByteValue')  # PrimitiveData
    byteValue.Value = (~byteValue.Value) & 0xFF
    print(byteValue.Value)
elif genericObject.DataTypeId.NodeDescriptor.Match(UANodeDescriptor('nsu=http://test.org/UA/Data/ ;i=9669')): # ArrayValueDataType
    # Negate bytes at indexes 0 and 1 of the array in the "ByteValue" field.
    structuredData = genericObject.GenericData
    byteValue = structuredData.FieldData.get_Item('ByteValue')  # SequenceData
    element0 = byteValue.Elements.get_Item(0)    # PrimitiveData
    element1 = byteValue.Elements.get_Item(1)    # PrimitiveData
    element0.Value = (~element0.Value) & 0xFF
    element1.Value = (~element1.Value) & 0xFF
    print(element0.Value)
    print(element1.Value)


# Write the modified complex data back to the node.
# The data type ID in the UAGenericObject is borrowed without change from what we have read, so that the server
# knows which data type we are writing. The data type ID not necessary if writing precisely the same data type
# as the node has (not a subtype).
try:
    print('Writing...')
    IEasyUAClientExtension.WriteValue(client, endpointDescriptor, nodeDescriptor, genericObject)
except UAException as uaException:
    print('*** Failure: ' + uaException.GetBaseException().Message)


print()
print('Finished.')

' Shows how to write complex data with OPC UA Complex Data plug-in.

Imports System
Imports OpcLabs.BaseLib.DataTypeModel
Imports OpcLabs.EasyOpc.UA
Imports OpcLabs.EasyOpc.UA.ComplexData
Imports OpcLabs.EasyOpc.UA.OperationModel

Namespace ComplexData._EasyUAClient

    Friend Class WriteValue

        Public Shared Sub Main1()

            ' 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/"

            ' Define which node we will work with.
            Dim nodeDescriptor As UANodeDescriptor = _
                "nsu=http://test.org/UA/Data/ ;i=10239"  ' [ObjectsFolder]/Data.Static.Scalar.StructureValue

            ' Instantiate the client object.
            Dim client = New EasyUAClient

            ' Read a node which returns complex data. 
            ' We know that this node returns complex data, so we can type cast to UAGenericObject.
            Console.WriteLine("Reading...")
            Dim genericObject As UAGenericObject
            Try
                genericObject = CType(client.ReadValue(endpointDescriptor, nodeDescriptor), UAGenericObject)
            Catch uaException As UAException
                Console.WriteLine("*** Failure: {0}", uaException.GetBaseException.Message)
                Exit Sub
            End Try


            ' Modify the data read.
            ' This node returns one of the two data types, randomly (this is not common, usually the type is fixed). The
            ' data types are sub-types of one common type which the data type of the node. We therefore use the data type 
            ' ID in the returned UAGenericObject to detect which data type has been returned.
            ' For processing the internals of the data, refer to examples for GenericData and DataType classes.
            ' We know how the data is structured, and have hard-coded a logic that modifies certain values inside. It is
            ' also possible to discover the structure of the data type in the program, and write generic clients that can 
            ' cope with any kind of complex data.
            '
            ' Note that the code below is not fully robust - it will throw an exception if the data is not as expected.
            Console.WriteLine("Modifying...")
            Console.WriteLine(genericObject.DataTypeId)
            If genericObject.DataTypeId.NodeDescriptor.Match("nsu=http://test.org/UA/Data/ ;i=9440") Then    ' ScalarValueDataType
                ' Negate the byte in the "ByteValue" field.
                Dim structuredData = CType(genericObject.GenericData, StructuredData)
                Dim byteValue = CType(structuredData.FieldData("ByteValue"), PrimitiveData)
                byteValue.Value = CType(Not CType(byteValue.Value, Byte), Byte)
                Console.WriteLine(byteValue.Value)
            ElseIf genericObject.DataTypeId.NodeDescriptor.Match("nsu=http://test.org/UA/Data/ ;i=9669") Then    ' ArrayValueDataType
                ' Negate bytes at indexes 0 and 1 of the array in the "ByteValue" field.
                Dim structuredData = CType(genericObject.GenericData, StructuredData)
                Dim byteValue = CType(structuredData.FieldData("ByteValue"), SequenceData)
                Dim element0 = CType(byteValue.Elements(0), PrimitiveData)
                Dim element1 = CType(byteValue.Elements(1), PrimitiveData)
                element0.Value = CType(Not CType(element0.Value, Byte), Byte)
                element1.Value = CType(Not CType(element1.Value, Byte), Byte)
                Console.WriteLine(element0.Value)
                Console.WriteLine(element1.Value)
            End If


            ' Write the modified complex data back to the node.
            ' The data type ID in the UAGenericObject is borrowed without change from what we have read, so that the server
            ' knows which data type we are writing. The data type ID not necessary if writing precisely the same data type
            ' as the node has (not a subtype).
            Console.WriteLine("Writing...")
            Try
                client.WriteValue(endpointDescriptor, nodeDescriptor, genericObject)
            Catch uaException As UAException
                Console.WriteLine("*** Failure: {0}", uaException.GetBaseException.Message)
                Exit Sub
            End Try
        End Sub
    End Class
End Namespace

Object Pascal
PHP

// Shows how to write complex data with OPC UA Complex Data plug-in.

class procedure WriteValue.Main;
var
  ArrayValueDataType: _UANodeDescriptor;
  ByteValue: _PrimitiveData;
  ByteValue2: _SequenceData;
  Client: _EasyUAClient;
  Element0, Element1: _PrimitiveData;
  EndpointDescriptor: string;
  GenericObject: _UAGenericObject;
  NodeDescriptor: string;
  ScalarValueDataType: _UANodeDescriptor;
  StructuredData: _StructuredData;
begin
  // Define which server and node we will work with.
  EndpointDescriptor := 
    //'http://opcua.demo-this.com:51211/UA/SampleServer';
    //'https://opcua.demo-this.com:51212/UA/SampleServer/';
    'opc.tcp://opcua.demo-this.com:51210/UA/SampleServer';
  NodeDescriptor := 'nsu=http://test.org/UA/Data/ ;i=10239';  // [ObjectsFolder]/Data.Static.Scalar.StructureValue

  // Instantiate the client object
  Client := CoEasyUAClient.Create;

  // Read a node which returns complex data.
  // We know that this node returns complex data, so we can type cast to UAGenericObject.
  WriteLn('Reading...');

  try
    GenericObject := _UAGenericObject(IUnknown(Client.ReadValue(EndpointDescriptor, NodeDescriptor)));
  except
    on E: EOleException do
    begin
      WriteLn(Format('*** Failure: %s', [E.GetBaseException.Message]));
      Exit;
    end;
  end;

  // Modify the data read.
  // This node returns one of the two data types, randomly (this is not common, usually the type is fixed). The
  // data types are sub-types of one common type which the data type of the node. We therefore use the data type
  // ID in the returned UAGenericObject to detect which data type has been returned.

  // For processing the internals of the data, refer to examples for GenericData and DataType classes.
  // We know how the data is structured, and have hard-coded a logic that modifies certain values inside. It is
  // also possible to discover the structure of the data type in the program, and write generic clients that can
  // cope with any kind of complex data.
  //
  // Note that the code below is not fully robust - it will throw an exception if the data is not as expected.

  WriteLn('Modifying...');
  WriteLn(GenericObject.DataTypeId.ToString);
  ScalarValueDataType := CoUANodeDescriptor.Create;
  ScalarValueDataType.NodeId.ExpandedText := 'nsu=http://test.org/UA/Data/ ;i=9440'; // ScalarValueDataType
  if GenericObject.DataTypeId.NodeDescriptor.Match(ScalarValueDataType) then
  begin
    // Negate the byte in the "ByteValue" field.
    StructuredData := IUnknown(GenericObject.GenericData) as _StructuredData;
    ByteValue := IUnknown(StructuredData.FieldData['ByteValue']) as _PrimitiveData;
    ByteValue.Value := Byte(not (Byte(byteValue.Value)));
    WriteLn(ByteValue.Value);
  end
  else
  begin
    ArrayValueDataType := CoUANodeDescriptor.Create;
    ArrayValueDataType.NodeId.ExpandedText := 'nsu=http://test.org/UA/Data/ ;i=9669'; // ArrayValueDataType
    if GenericObject.DataTypeId.Nodedescriptor.Match(ArrayValueDataType) then
    begin
      // Negate bytes at indexes 0 and 1 of the array in the "ByteValue" field.
      StructuredData := IUnknown(GenericObject.GenericData) as _StructuredData;
      ByteValue2 := IUnknown(StructuredData.FieldData['ByteValue']) as _SequenceData;
      Element0 := IUnknown(ByteValue2.Elements[0]) as _PrimitiveData;
      Element1 := IUnknown(ByteValue2.Elements[1]) as _PrimitiveData;
      Element0.Value := Byte(not (Byte(element0.Value)));
      Element1.Value := Byte(not (Byte(element1.Value)));
      WriteLn(Element0.Value);
      WriteLn(Element1.Value);
    end;
  end;

  // Write the modified complex data back to the node.
  // The data type ID in the UAGenericObject is borrowed without change from what we have read, so that the server
  // knows which data type we are writing. The data type ID not necessary if writing precisely the same data type
  // as the node has (not a subtype).
  WriteLn('Writing...');
  try
    Client.WriteValue(EndpointDescriptor, NodeDescriptor, GenericObject);
  except
    on E: EOleException do
    begin
      WriteLn(Format('*** Failure: %s', [E.GetBaseException.Message]));
      Exit;
    end;
  end;

end;

// Shows how to write complex data with OPC UA Complex Data plug-in.

// Define which server and node we will work with.
$EndpointDescriptor = 
    //"http://opcua.demo-this.com:51211/UA/SampleServer";
    //"https://opcua.demo-this.com:51212/UA/SampleServer/";
    "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer";
$NodeDescriptor = "nsu=http://test.org/UA/Data/ ;i=10239";  // [ObjectsFolder]/Data.Static.Scalar.StructureValue

// Instantiate the client object
$Client = new COM("OpcLabs.EasyOpc.UA.EasyUAClient");

// Read a node which returns complex data.
// We know that this node returns complex data, so we can type cast to UAGenericObject.
printf("Reading...\n");

try
{
    $GenericObject = $Client->ReadValue($EndpointDescriptor, $NodeDescriptor);
}
catch (com_exception $e)
{
    printf("*** Failure: %s\n", $e->getMessage());
    Exit();
}

// Modify the data read.
// This node returns one of the two data types, randomly (this is not common, usually the type is fixed). The
// data types are sub-types of one common type which the data type of the node. We therefore use the data type
// ID in the returned UAGenericObject to detect which data type has been returned.

// For processing the internals of the data, refer to examples for GenericData and DataType classes.
// We know how the data is structured, and have hard-coded a logic that modifies certain values inside. It is
// also possible to discover the structure of the data type in the program, and write generic clients that can
// cope with any kind of complex data.
//
// Note that the code below is not fully robust - it will throw an exception if the data is not as expected.

printf("Modifying...\n");
printf("%s\n", $GenericObject->DataTypeId);
$ScalarValueDataType = new COM("OpcLabs.EasyOpc.UA.UANodeDescriptor");
$ScalarValueDataType->NodeId->ExpandedText = "nsu=http://test.org/UA/Data/ ;i=9440"; // ScalarValueDataType
if ($GenericObject->DataTypeId->NodeDescriptor->Match($ScalarValueDataType)) {
    // Negate the byte in the "ByteValue" field.
    $StructuredData = $GenericObject->GenericData->AsStructuredData();
    $ByteValue = $StructuredData->FieldData["ByteValue"]->AsPrimitiveData();
    $ByteValue->Value = ~($ByteValue->Value) & 255;
    printf("%s\n", $ByteValue->Value);
}
else {
    $ArrayValueDataType = new COM("OpcLabs.EasyOpc.UA.UANodeDescriptor");
    $ArrayValueDataType->NodeId->ExpandedText = "nsu=http://test.org/UA/Data/ ;i=9669"; // ArrayValueDataType
    if ($GenericObject->DataTypeId->Nodedescriptor->Match($ArrayValueDataType)) {
        // Negate bytes at indexes 0 and 1 of the array in the "ByteValue" field.
        $StructuredData = $GenericObject->GenericData->AsStructuredData();
        $ByteValue2 = $StructuredData->FieldData["ByteValue"]->AsSequenceData();
        $Element0 = $ByteValue2->Elements[0]->AsPrimitiveData();
        $Element1 = $ByteValue2->Elements[1]->AsPrimitiveData();
        $Element0->Value = ~($Element0->Value) & 255;
        $Element1->Value = ~($Element1->Value) & 255;
        printf("%s\n", $Element0->Value);
        printf("%s\n", $Element1->Value);
    }
}

// Write the modified complex data back to the node.
// The data type ID in the UAGenericObject is borrowed without change from what we have read, so that the server
// knows which data type we are writing. The data type ID not necessary if writing precisely the same data type
// as the node has (not a subtype).
printf("Writing...\n");
try
{
    $Client->WriteValue($EndpointDescriptor, $NodeDescriptor, $GenericObject);
}
catch (com_exception $e)
{
    printf("Failure: %s\n", $e->getMessage());
    Exit();
}

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

_UANodeDescriptor Interface
_UANodeDescriptor Members

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