OPC Studio User's Guide and Reference
Examples - OPC UA Complex Data - Write a value

The example below first reads a structured value from the server, and then manipulates (changes) its elements. The modified value is then written to the server. In this case, the data type ID (and also the data type) can be taken over from what has been provided by the Read.

.NET

// Shows how to write complex data with OPC UA Complex Data plug-in.
//
// Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .

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.
#
# 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 .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.
'
' Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .

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

COM

// Shows how to write complex data with OPC UA Complex Data plug-in.
//
// Find all latest examples here : https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .

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.
//
// Find all latest examples here : https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .

// 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();
}

 

See Also
Examples - OPC UA Complex Data - Read a value
Examples - OPC UA Complex Data - Create generic data

Examples - OPC UA Layered Extensions

Examples - OPC UA Layered Extensions - Retrieve sub-types of a data type

Conceptual

OPC UA Complex Data writing

Examples - OPC Unified Architecture

Examples - OPC Unified Architecture - Write a single value

 

 

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