OPC Studio User's Guide and Reference
WriteMultiple Method (EasyUAClientCore)
Example 



OpcLabs.EasyOpcUA Assembly > OpcLabs.EasyOpc.UA Namespace > EasyUAClientCore Class : WriteMultiple Method
Array of OpcLabs.EasyOpc.UA.OperationModel.UAWriteArguments. Array of argument objects specifying what to write from an OPC-UA server.
Writes data into multiple attributes, using array of argument objects as an input.
Syntax
'Declaration
 
Public Function WriteMultiple( _
   ByVal writeArgumentsArray() As UAWriteArguments _
) As UAWriteResult()
'Usage
 
Dim instance As EasyUAClientCore
Dim writeArgumentsArray() As UAWriteArguments
Dim value() As UAWriteResult
 
value = instance.WriteMultiple(writeArgumentsArray)

Parameters

writeArgumentsArray
Array of OpcLabs.EasyOpc.UA.OperationModel.UAWriteArguments. Array of argument objects specifying what to write from an OPC-UA server.

Return Value

Array of OpcLabs.EasyOpc.UA.OperationModel.UAWriteResult. The method returns an array of OpcLabs.EasyOpc.UA.OperationModel.UAWriteResult objects. The indices of elements in the output array are the same as those in the input arrays.

 

This is a multiple-operation method. In a properly written program, it does not throw any exceptions. You should therefore not put try/catch statements or similar constructs around calls to this method. The only exceptions thrown by this method are for usage errors, i.e. when your code violates the usage contract of the method, such as passing in invalid arguments or calling the method when the state of the object does not allow it. Any operation-related errors (i.e. errors that depend on external conditions that your code cannot reliably check) are indicated in the result objects returned by the method. For more information, see Multiple-operation Methods and Do not catch any exceptions with asynchronous or multiple-operation methods.
Exceptions
ExceptionDescription

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

The size of the input array will become the size of the output array. The element positions (indices) in the output array are the same as in the input array.

This method does not throw an exception in case of OPC operation failures. Instead, the eventual exception related to each item is returned in Exception property of each returned OpcLabs.EasyOpc.UA.OperationModel.UAWriteResult element.

Example

.NET

// This example shows how to write data (a value, timestamps and status code) into 3 nodes at once, test for success of each 
// write and display the exception message in case of failure.
//
// Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .

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

namespace UADocExamples._EasyUAClient
{
    class WriteMultiple
    {
        public static void TestSuccess()
        {
            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
            var client = new EasyUAClient();

            // Modify data of nodes' attributes
            OperationResult[] operationResultArray = client.WriteMultiple(new[]
                {
                    new UAWriteArguments(endpointDescriptor, "nsu=http://test.org/UA/Data/ ;i=10221", 
                        new UAAttributeData(23456, UASeverity.GoodOrSuccess, DateTime.UtcNow)),
                    new UAWriteArguments(endpointDescriptor, "nsu=http://test.org/UA/Data/ ;i=10226", 
                        new UAAttributeData(2.34567890, UASeverity.GoodOrSuccess, DateTime.UtcNow)),
                    new UAWriteArguments(endpointDescriptor, "nsu=http://test.org/UA/Data/ ;i=10227", 
                        new UAAttributeData("ABC", UASeverity.GoodOrSuccess, DateTime.UtcNow))
                });

            // The target server may not support this, and in such case failures will occur.

            for (int i = 0; i < operationResultArray.Length; i++)
                if (operationResultArray[i].Succeeded)
                    Console.WriteLine("Result {0}: success", i);
                else
                    Console.WriteLine("Result {0}: {1}", i, operationResultArray[i].Exception.GetBaseException().Message);
        }
    }
}
# This example shows how to write data (a value, timestamps and status code) into 3 nodes at once, test for success of
# each write and display the exception message in case of failure.
#
# 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.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/'

# Instantiate the client object
client = EasyUAClient()

print("Modifying data of nodes' attributes...")
writeResultArray = client.WriteMultiple([
    UAWriteArguments(endpointDescriptor, UANodeDescriptor('nsu=http://test.org/UA/Data/ ;i=10221'),
                     UAAttributeData(23456, UAStatusCode(UASeverity.GoodOrSuccess), DateTime.UtcNow)),
    UAWriteArguments(endpointDescriptor, UANodeDescriptor('nsu=http://test.org/UA/Data/ ;i=10226'),
                     UAAttributeData(2.34567890, UAStatusCode(UASeverity.GoodOrSuccess), DateTime.UtcNow)),
    UAWriteArguments(endpointDescriptor, UANodeDescriptor('nsu=http://test.org/UA/Data/ ;i=10227'),
                     UAAttributeData('ABC', UAStatusCode(UASeverity.GoodOrSuccess), DateTime.UtcNow)),
    ])

# The target server may not support this, and in such case failures will occur.
for i, writeResult in enumerate(writeResultArray):
    if writeResult.Succeeded:
        print('writeResultArray[', i, ']: success', sep='')
    else:
        print('writeResultArray[', i, '] *** Failure: ', writeResult.Exception.GetBaseException().Message, sep='')

print()
print('Finished.')
' This example shows how to write data (a value, timestamps and status code) into 3 nodes at once, test for success of each 
' write and display the exception message in case of failure.
'
' Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .

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

Namespace _EasyUAClient
    Friend Class WriteMultiple
        Public Shared Sub TestSuccess()

            ' 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
            Dim client = New EasyUAClient()

            ' Modify data of nodes' attributes
            Dim operationResultArray() As OperationResult = client.WriteMultiple(New UAWriteArguments() _
              {
                  New UAWriteArguments(endpointDescriptor, "nsu=http://test.org/UA/Data/ ;i=10221",
                                       New UAAttributeData(23456, UASeverity.GoodOrSuccess, Date.UtcNow)),
                  New UAWriteArguments(endpointDescriptor, "nsu=http://test.org/UA/Data/ ;i=10226",
                                       New UAAttributeData(2.3456789, UASeverity.GoodOrSuccess, Date.UtcNow)),
                  New UAWriteArguments(endpointDescriptor, "nsu=http://test.org/UA/Data/ ;i=10227",
                                       New UAAttributeData("ABC", UASeverity.GoodOrSuccess, Date.UtcNow))
              }
            )

            ' The target server may not support this, and in such case failures will occur.

            For i As Integer = 0 To operationResultArray.Length - 1
                If operationResultArray(i).Succeeded Then
                    Console.WriteLine("Result {0}: success", i)
                Else
                    Console.WriteLine("Result {0}: {1}", i, operationResultArray(i).Exception.GetBaseException().Message)
                End If
            Next i
        End Sub
    End Class
End Namespace
Requirements

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

See Also