ReadMultiple Method (

Reads multiple attributes, using array of argument objects as an input.

Syntax

[JetBrains.Annotations.ItemNotNull()]
[JetBrains.Annotations.NotNull()]
object[] ReadMultiple( 
   object readArgumentsArray
)

[JetBrains.Annotations.ItemNotNull()]
[JetBrains.Annotations.NotNull()]
array<Object^>^ ReadMultiple( 
   Object^ readArgumentsArray
)

'Declaration
 
<JetBrains.Annotations.ItemNotNullAttribute()>
<JetBrains.Annotations.NotNullAttribute()>
Function ReadMultiple( _
   ByVal readArgumentsArray As Object _
) As Object()

'Usage
 
Dim instance As _EasyUAClient
Dim readArgumentsArray As Object
Dim value() As Object
 
value = instance.ReadMultiple(readArgumentsArray)

Parameters

readArgumentsArray

Array of OpcLabs.EasyOpc.UA.OperationModel.UAReadArguments. Array of argument objects specifying what to read from an OPC-UA server.

The value of this parameter cannot be null (Nothing in Visual Basic).

The individual elements of the parameter value cannot be null (Nothing in Visual Basic).

Return Value

Array of OpcLabs.EasyOpc.UA.OperationModel.UAAttributeDataResult. Returns an array of attribute data objects. Each object stores the value of an attribute, together with status code and timestamps. The indices of elements in the output array are the same as those in the input array, .

This method never returns null (Nothing in Visual Basic).

The individual elements of the returned value are never null (Nothing in Visual Basic).

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.ObjectDisposedException	An operation was performed on a disposed object.

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.ObjectDisposedException An operation was performed on a disposed object.

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.

Each element in the input array corresponds to a separate logical read operation (although the operations may and will be executed together, if possible). The method returns an array of results, where each result corresponds to the read operation at the same index in the input array.

This member or type is for use from COM. It is not meant to be used from .NET or Python. Refer to the corresponding .NET member or type instead, if you are developing in .NET or Python.

Example

COM

// This example shows how to read the attributes of 4 OPC-UA nodes at once, and display the results.
//
// Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .
// Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own
// a commercial license in order to use Online Forums, and we reply to every post.

#include "stdafx.h"    // Includes "QuickOpc.h", and other commonly used files
#include <atlsafe.h>
#include "ReadMultiple.h"

namespace _EasyUAClient
{
    void ReadMultiple::Main()
    {
        // Initialize the COM library
        CoInitializeEx(NULL, COINIT_MULTITHREADED);
        {
            _UAReadArgumentsPtr ReadArguments1Ptr(_uuidof(UAReadArguments));
            ReadArguments1Ptr->EndpointDescriptor->UrlString = 
                //L"http://opcua.demo-this.com:51211/UA/SampleServer";
                L"opc.tcp://opcua.demo-this.com:51210/UA/SampleServer";
            ReadArguments1Ptr->NodeDescriptor->NodeId->ExpandedText = L"nsu=http://test.org/UA/Data/ ;i=10853";

            _UAReadArgumentsPtr ReadArguments2Ptr(_uuidof(UAReadArguments));
            ReadArguments2Ptr->EndpointDescriptor->UrlString = 
                //L"http://opcua.demo-this.com:51211/UA/SampleServer";
                L"opc.tcp://opcua.demo-this.com:51210/UA/SampleServer";
            ReadArguments2Ptr->NodeDescriptor->NodeId->ExpandedText = L"nsu=http://test.org/UA/Data/ ;i=10845";

            _UAReadArgumentsPtr ReadArguments3Ptr(_uuidof(UAReadArguments));
            ReadArguments3Ptr->EndpointDescriptor->UrlString = 
                //L"http://opcua.demo-this.com:51211/UA/SampleServer";
                L"opc.tcp://opcua.demo-this.com:51210/UA/SampleServer";
            ReadArguments3Ptr->NodeDescriptor->NodeId->ExpandedText = L"nsu=http://test.org/UA/Data/ ;i=10304";

            _UAReadArgumentsPtr ReadArguments4Ptr(_uuidof(UAReadArguments));
            ReadArguments4Ptr->EndpointDescriptor->UrlString = 
                //L"http://opcua.demo-this.com:51211/UA/SampleServer";
                L"opc.tcp://opcua.demo-this.com:51210/UA/SampleServer";
            ReadArguments4Ptr->NodeDescriptor->NodeId->ExpandedText = L"nsu=http://test.org/UA/Data/ ;i=10389";

            CComSafeArray<VARIANT> arguments(4);
            arguments.SetAt(0, _variant_t((IDispatch*)ReadArguments1Ptr));
            arguments.SetAt(1, _variant_t((IDispatch*)ReadArguments2Ptr));
            arguments.SetAt(2, _variant_t((IDispatch*)ReadArguments3Ptr));
            arguments.SetAt(3, _variant_t((IDispatch*)ReadArguments4Ptr));
            CComVariant vArguments(arguments);

            // Instantiate the client object
            _EasyUAClientPtr ClientPtr(__uuidof(EasyUAClient));

            // Obtain values. By default, the Value attributes of the nodes will be read.
            CComSafeArray<VARIANT> results;
            results.Attach(ClientPtr->ReadMultiple(&vArguments));
            
            // Display results
            for (int i = results.GetLowerBound(); i <= results.GetUpperBound(); i++)
            {
                _UAAttributeDataResultPtr ResultPtr = results[i];

                _variant_t vString;
                vString.ChangeType(VT_BSTR, &_variant_t((IDispatch*)ResultPtr->AttributeData));
                _tprintf(_T("results(d).AttributeDatas\n"), i, (LPCTSTR)CW2CT((_bstr_t)vString));
            }
        }
         // Release all interface pointers BEFORE calling CoUninitialize()
        CoUninitialize();
    }
}

// This example shows how to read the attributes of 4 OPC-UA nodes at once, and
// display the results.
//
// Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .
// Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own
// a commercial license in order to use Online Forums, and we reply to every post.

class procedure ReadMultiple.Main;
var
  Arguments: OleVariant;
  Client: EasyUAClient;
  I: Cardinal;
  ReadArguments1, ReadArguments2, ReadArguments3, ReadArguments4: _UAReadArguments;
  Result: _UAAttributeDataResult;
  Results: OleVariant;
begin
  ReadArguments1 := CoUAReadArguments.Create;
  ReadArguments1.EndpointDescriptor.UrlString := 
      //'http://opcua.demo-this.com:51211/UA/SampleServer';
    'opc.tcp://opcua.demo-this.com:51210/UA/SampleServer';
  ReadArguments1.NodeDescriptor.NodeId.ExpandedText := 'nsu=http://test.org/UA/Data/ ;i=10853';

  ReadArguments2 := CoUAReadArguments.Create;
  ReadArguments2.EndpointDescriptor.UrlString := 
      //'http://opcua.demo-this.com:51211/UA/SampleServer';
    'opc.tcp://opcua.demo-this.com:51210/UA/SampleServer';
  ReadArguments2.NodeDescriptor.NodeId.ExpandedText := 'nsu=http://test.org/UA/Data/ ;i=10845';

  ReadArguments3 := CoUAReadArguments.Create;
  ReadArguments3.EndpointDescriptor.UrlString := 
      //'http://opcua.demo-this.com:51211/UA/SampleServer';
    'opc.tcp://opcua.demo-this.com:51210/UA/SampleServer';
  ReadArguments3.NodeDescriptor.NodeId.ExpandedText := 'nsu=http://test.org/UA/Data/ ;i=10304';

  ReadArguments4 := CoUAReadArguments.Create;
  ReadArguments4.EndpointDescriptor.UrlString := 
      //'http://opcua.demo-this.com:51211/UA/SampleServer';
    'opc.tcp://opcua.demo-this.com:51210/UA/SampleServer';
  ReadArguments4.NodeDescriptor.NodeId.ExpandedText := 'nsu=http://test.org/UA/Data/ ;i=10389';

  Arguments := VarArrayCreate([0, 3], varVariant);
  Arguments[0] := ReadArguments1;
  Arguments[1] := ReadArguments2;
  Arguments[2] := ReadArguments3;
  Arguments[3] := ReadArguments4;

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

  // Perform the operation
  TVarData(Results).VType := varArray or varVariant;
  TVarData(Results).VArray := PVarArray(Client.ReadMultiple(
    PSafeArray(TVarData(Arguments).VArray)));

  // Display results
  for I := VarArrayLowBound(Results, 1) to VarArrayHighBound(Results, 1) do
  begin
    Result := IInterface(Results[I]) as _UAAttributeDataResult;
    WriteLn('results(', I, ').AttributeData: ', Result.AttributeData.ToString);
  end;
end;

// This example shows how to read the attributes of 4 OPC-UA nodes at once, and
// display the results.
//
// Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .
// OPC client and subscriber examples in Object Pascal (Delphi) on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-OP .
// Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own
// a commercial license in order to use Online Forums, and we reply to every post.

class procedure ReadMultiple.Main;
var
  Arguments: OleVariant;
  Client: OpcLabs_EasyOpcUA_TLB._EasyUAClient;
  I: Cardinal;
  ReadArguments1, ReadArguments2, ReadArguments3, ReadArguments4: _UAReadArguments;
  Result: _UAAttributeDataResult;
  Results: OleVariant;
begin
  ReadArguments1 := CoUAReadArguments.Create;
  ReadArguments1.EndpointDescriptor.UrlString := 
    //'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';
  ReadArguments1.NodeDescriptor.NodeId.ExpandedText := 'nsu=http://test.org/UA/Data/ ;i=10853';

  ReadArguments2 := CoUAReadArguments.Create;
  ReadArguments2.EndpointDescriptor.UrlString := 
    //'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';
  ReadArguments2.NodeDescriptor.NodeId.ExpandedText := 'nsu=http://test.org/UA/Data/ ;i=10845';

  ReadArguments3 := CoUAReadArguments.Create;
  ReadArguments3.EndpointDescriptor.UrlString := 
    //'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';
  ReadArguments3.NodeDescriptor.NodeId.ExpandedText := 'nsu=http://test.org/UA/Data/ ;i=10304';

  ReadArguments4 := CoUAReadArguments.Create;
  ReadArguments4.EndpointDescriptor.UrlString := 
    //'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';
  ReadArguments4.NodeDescriptor.NodeId.ExpandedText := 'nsu=http://test.org/UA/Data/ ;i=10389';

  Arguments := VarArrayCreate([0, 3], varVariant);
  Arguments[0] := ReadArguments1;
  Arguments[1] := ReadArguments2;
  Arguments[2] := ReadArguments3;
  Arguments[3] := ReadArguments4;

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

  // Perform the operation
  TVarData(Results).VType := varArray or varVariant;
  TVarData(Results).VArray := PVarArray(Client.ReadMultiple(Arguments));

  // Display results
  for I := VarArrayLowBound(Results, 1) to VarArrayHighBound(Results, 1) do
  begin
    Result := IInterface(Results[I]) as _UAAttributeDataResult;
    if Result.Succeeded then
      WriteLn('results(', I, ').AttributeData: ', Result.AttributeData.ToString)
    else
      WriteLn('results(', I, ') *** Failure: ', Result.ErrorMessageBrief);
  end;

  VarClear(Results);
  VarClear(Arguments);
end;

// This example shows how to read the attributes of 4 OPC-UA nodes at once, and display the results.
//
// Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .
// OPC client and subscriber examples in PHP on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-PHP .
// Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own
// a commercial license in order to use Online Forums, and we reply to every post.

$ReadArguments1 = new COM("OpcLabs.EasyOpc.UA.OperationModel.UAReadArguments");
$ReadArguments1->EndpointDescriptor->UrlString = 
    //"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";
$ReadArguments1->NodeDescriptor->NodeId->ExpandedText = "nsu=http://test.org/UA/Data/ ;i=10853";

$ReadArguments2 = new COM("OpcLabs.EasyOpc.UA.OperationModel.UAReadArguments");
$ReadArguments2->EndpointDescriptor->UrlString = 
    //"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";
$ReadArguments2->NodeDescriptor->NodeId->ExpandedText = "nsu=http://test.org/UA/Data/ ;i=10845";

$ReadArguments3 = new COM("OpcLabs.EasyOpc.UA.OperationModel.UAReadArguments");
$ReadArguments3->EndpointDescriptor->UrlString = 
    //"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";
$ReadArguments3->NodeDescriptor->NodeId->ExpandedText = "nsu=http://test.org/UA/Data/ ;i=10304";

$ReadArguments4 = new COM("OpcLabs.EasyOpc.UA.OperationModel.UAReadArguments");
$ReadArguments4->EndpointDescriptor->UrlString = 
    //"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";
$ReadArguments4->NodeDescriptor->NodeId->ExpandedText = "nsu=http://test.org/UA/Data/ ;i=10389";

$arguments[0] = $ReadArguments1;
$arguments[1] = $ReadArguments2;
$arguments[2] = $ReadArguments3;
$arguments[3] = $ReadArguments4;

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

// Perform the operation
$results = $Client->ReadMultiple($arguments);

// Display results
for ($i = 0; $i < count($results); $i++)
{
    $attributeDataResult = $results[$i];
    if ($attributeDataResult->Succeeded)
        printf("results[d].AttributeDatas\n", $i, $attributeDataResult->AttributeData);
    else
        printf("results[d]: *** Failures\n", $i, $attributeDataResult->ErrorMessageBrief);
}

REM This example shows how to read the attributes of 4 OPC-UA nodes at once, and
REM display the results.
REM
REM Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .
REM OPC client and subscriber examples in Visual Basic on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-VB .
REM Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own
REM a commercial license in order to use Online Forums, and we reply to every post.

Public Sub ReadMultiple_Main_Command_Click()
    OutputText = ""

    Dim readArguments1 As New UAReadArguments
    readArguments1.endpointDescriptor.UrlString = "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer"
    readArguments1.nodeDescriptor.NodeId.expandedText = "nsu=http://test.org/UA/Data/ ;i=10853"

    Dim ReadArguments2 As New UAReadArguments
    ReadArguments2.endpointDescriptor.UrlString = "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer"
    ReadArguments2.nodeDescriptor.NodeId.expandedText = "nsu=http://test.org/UA/Data/ ;i=10845"

    Dim ReadArguments3 As New UAReadArguments
    ReadArguments3.endpointDescriptor.UrlString = "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer"
    ReadArguments3.nodeDescriptor.NodeId.expandedText = "nsu=http://test.org/UA/Data/ ;i=10304"

    Dim ReadArguments4 As New UAReadArguments
    ReadArguments4.endpointDescriptor.UrlString = "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer"
    ReadArguments4.nodeDescriptor.NodeId.expandedText = "nsu=http://test.org/UA/Data/ ;i=10389"

    Dim arguments(3) As Variant
    Set arguments(0) = readArguments1
    Set arguments(1) = ReadArguments2
    Set arguments(2) = ReadArguments3
    Set arguments(3) = ReadArguments4

    ' Instantiate the client object
    Dim Client As New EasyUAClient

    ' Obtain values. By default, the Value attributes of the nodes will be read.
    Dim results() As Variant
    results = Client.ReadMultiple(arguments)

    ' Display results
    Dim i: For i = LBound(results) To UBound(results)
        Dim Result As UAAttributeDataResult: Set Result = results(i)
        If Result.Succeeded Then
            OutputText = OutputText & "results(" & i & ").AttributeData: " & Result.AttributeData & vbCrLf
        Else
            OutputText = OutputText & "results(" & i & ") *** Failure: " & Result.ErrorMessageBrief & vbCrLf
        End If
    Next
End Sub

Rem This example shows how to read the attributes of 4 OPC-UA nodes at once, and display the results.
Rem
Rem Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .
Rem OPC client and subscriber examples in VBScript on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-VBScript .
Rem Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own
Rem a commercial license in order to use Online Forums, and we reply to every post.

Option Explicit

Dim ReadArguments1: Set ReadArguments1 = CreateObject("OpcLabs.EasyOpc.UA.OperationModel.UAReadArguments")
ReadArguments1.EndpointDescriptor.UrlString = "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer"
ReadArguments1.NodeDescriptor.NodeId.ExpandedText = "nsu=http://test.org/UA/Data/ ;i=10853"

Dim ReadArguments2: Set ReadArguments2 = CreateObject("OpcLabs.EasyOpc.UA.OperationModel.UAReadArguments")
ReadArguments2.EndpointDescriptor.UrlString = "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer"
ReadArguments2.NodeDescriptor.NodeId.ExpandedText = "nsu=http://test.org/UA/Data/ ;i=10845"

Dim ReadArguments3: Set ReadArguments3 = CreateObject("OpcLabs.EasyOpc.UA.OperationModel.UAReadArguments")
ReadArguments3.EndpointDescriptor.UrlString = "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer"
ReadArguments3.NodeDescriptor.NodeId.ExpandedText = "nsu=http://test.org/UA/Data/ ;i=10304"

Dim ReadArguments4: Set ReadArguments4 = CreateObject("OpcLabs.EasyOpc.UA.OperationModel.UAReadArguments")
ReadArguments4.EndpointDescriptor.UrlString = "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer"
ReadArguments4.NodeDescriptor.NodeId.ExpandedText = "nsu=http://test.org/UA/Data/ ;i=10389"

Dim arguments(3)
Set arguments(0) = ReadArguments1
Set arguments(1) = ReadArguments2
Set arguments(2) = ReadArguments3
Set arguments(3) = ReadArguments4

' Instantiate the client object
Dim Client: Set Client = CreateObject("OpcLabs.EasyOpc.UA.EasyUAClient")

' Perform the operation
Dim results: results = Client.ReadMultiple(arguments)

' Display results
Dim i: For i = LBound(results) To UBound(results)
    Dim AttributeDataResult: Set AttributeDataResult = results(i)
    If AttributeDataResult.Succeeded Then
        WScript.Echo "results(" & i & ").AttributeData: " & AttributeDataResult.AttributeData
    Else
        WScript.Echo "results(" & i & ") *** Failure: " & AttributeDataResult.ErrorMessageBrief
    End If
Next

// This example shows how to read the attributes of 4 OPC-UA nodes specified by browse paths at once, and display the results.
//
// Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .
// Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own
// a commercial license in order to use Online Forums, and we reply to every post.

#include "stdafx.h"    // Includes "QuickOpc.h", and other commonly used files
#include <atlsafe.h>
#include "ReadMultiple.h"

namespace _EasyUAClient
{
    void ReadMultiple::BrowsePath()
    {
        // Initialize the COM library
        CoInitializeEx(NULL, COINIT_MULTITHREADED);
        {
            _UABrowsePathParserPtr BrowsePathParserPtr(_uuidof(UABrowsePathParser));
            BrowsePathParserPtr->DefaultNamespaceUriString = L"http://test.org/UA/Data/";

            _UAReadArgumentsPtr ReadArguments1Ptr(_uuidof(UAReadArguments));
            ReadArguments1Ptr->EndpointDescriptor->UrlString = 
                //L"http://opcua.demo-this.com:51211/UA/SampleServer";
                L"opc.tcp://opcua.demo-this.com:51210/UA/SampleServer";
            ReadArguments1Ptr->NodeDescriptor->BrowsePath = 
                BrowsePathParserPtr->Parse(L"[ObjectsFolder]/Data/Dynamic/Scalar/FloatValue");

            _UAReadArgumentsPtr ReadArguments2Ptr(_uuidof(UAReadArguments));
            ReadArguments2Ptr->EndpointDescriptor->UrlString = 
                //L"http://opcua.demo-this.com:51211/UA/SampleServer";
                L"opc.tcp://opcua.demo-this.com:51210/UA/SampleServer";
            ReadArguments2Ptr->NodeDescriptor->BrowsePath =
                BrowsePathParserPtr->Parse(L"[ObjectsFolder]/Data/Dynamic/Scalar/SByteValue");

            _UAReadArgumentsPtr ReadArguments3Ptr(_uuidof(UAReadArguments));
            ReadArguments3Ptr->EndpointDescriptor->UrlString = 
                //L"http://opcua.demo-this.com:51211/UA/SampleServer";
                L"opc.tcp://opcua.demo-this.com:51210/UA/SampleServer";
            ReadArguments3Ptr->NodeDescriptor->BrowsePath =
                BrowsePathParserPtr->Parse(L"[ObjectsFolder]/Data/Static/Array/UInt16Value");

            _UAReadArgumentsPtr ReadArguments4Ptr(_uuidof(UAReadArguments));
            ReadArguments4Ptr->EndpointDescriptor->UrlString = 
                //L"http://opcua.demo-this.com:51211/UA/SampleServer";
                L"opc.tcp://opcua.demo-this.com:51210/UA/SampleServer";
            ReadArguments4Ptr->NodeDescriptor->BrowsePath =
                BrowsePathParserPtr->Parse(L"[ObjectsFolder]/Data/Static/UserScalar/Int32Value");

            CComSafeArray<VARIANT> arguments(4);
            arguments.SetAt(0, _variant_t((IDispatch*)ReadArguments1Ptr));
            arguments.SetAt(1, _variant_t((IDispatch*)ReadArguments2Ptr));
            arguments.SetAt(2, _variant_t((IDispatch*)ReadArguments3Ptr));
            arguments.SetAt(3, _variant_t((IDispatch*)ReadArguments4Ptr));
            CComVariant vArguments(arguments);

            // Instantiate the client object
            _EasyUAClientPtr ClientPtr(__uuidof(EasyUAClient));

            // Obtain values. By default, the Value attributes of the nodes will be read.
            CComSafeArray<VARIANT> results;
            results.Attach(ClientPtr->ReadMultiple(&vArguments));
            
            // Display results
            for (int i = results.GetLowerBound(); i <= results.GetUpperBound(); i++)
            {
                _UAAttributeDataResultPtr ResultPtr = results[i];

                _variant_t vString;
                vString.ChangeType(VT_BSTR, &_variant_t((IDispatch*)ResultPtr->AttributeData));
                _tprintf(_T("results(d).AttributeDatas\n"), i, (LPCTSTR)CW2CT((_bstr_t)vString));
            }
        }
         // Release all interface pointers BEFORE calling CoUninitialize()
        CoUninitialize();
    }
}

// This example shows how to read the attributes of 4 OPC-UA nodes specified
// by browse paths at once, and display the results.
//
// Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .
// OPC client and subscriber examples in Object Pascal (Delphi) on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-OP .
// Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own
// a commercial license in order to use Online Forums, and we reply to every post.

class procedure ReadMultiple.BrowsePath;
var
  Arguments: OleVariant;
  BrowsePathParser: _UABrowsePathParser;
  Client: OpcLabs_EasyOpcUA_TLB._EasyUAClient;
  I: Cardinal;
  ReadArguments1, ReadArguments2, ReadArguments3, ReadArguments4: _UAReadArguments;
  Result: _UAAttributeDataResult;
  Results: OleVariant;
begin
  BrowsePathParser := CoUABrowsePathParser.Create;
  BrowsePathParser.DefaultNamespaceUriString := 'http://test.org/UA/Data/';

  ReadArguments1 := CoUAReadArguments.Create;
  ReadArguments1.EndpointDescriptor.UrlString := 
    //'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';
  //  Note: Add error handling around the following statement if the browse path is not guaranteed to be syntactically valid.
  ReadArguments1.NodeDescriptor.BrowsePath := BrowsePathParser.Parse('[ObjectsFolder]/Data/Dynamic/Scalar/FloatValue');

  ReadArguments2 := CoUAReadArguments.Create;
  ReadArguments2.EndpointDescriptor.UrlString := 
    //'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';
  //  Note: Add error handling around the following statement if the browse path is not guaranteed to be syntactically valid.
  ReadArguments2.NodeDescriptor.BrowsePath := BrowsePathParser.Parse('[ObjectsFolder]/Data/Dynamic/Scalar/SByteValue');

  ReadArguments3 := CoUAReadArguments.Create;
  ReadArguments3.EndpointDescriptor.UrlString := 
    //'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';
  //  Note: Add error handling around the following statement if the browse path is not guaranteed to be syntactically valid.
  ReadArguments3.NodeDescriptor.BrowsePath := BrowsePathParser.Parse('[ObjectsFolder]/Data/Static/Array/UInt16Value');

  ReadArguments4 := CoUAReadArguments.Create;
  ReadArguments4.EndpointDescriptor.UrlString := 
    //'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';
  //  Note: Add error handling around the following statement if the browse path is not guaranteed to be syntactically valid.
  ReadArguments4.NodeDescriptor.BrowsePath := BrowsePathParser.Parse('[ObjectsFolder]/Data/Static/UserScalar/Int32Value');

  Arguments := VarArrayCreate([0, 3], varVariant);
  Arguments[0] := ReadArguments1;
  Arguments[1] := ReadArguments2;
  Arguments[2] := ReadArguments3;
  Arguments[3] := ReadArguments4;

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

  // Perform the operation
  TVarData(Results).VType := varArray or varVariant;
  TVarData(Results).VArray := PVarArray(Client.ReadMultiple(Arguments));

  // Display results
  for I := VarArrayLowBound(Results, 1) to VarArrayHighBound(Results, 1) do
  begin
    Result := IInterface(Results[I]) as _UAAttributeDataResult;
    if Result.Succeeded then
      WriteLn('results[', I, '].AttributeData: ', Result.AttributeData.ToString)
    else
      WriteLn('results[', I, '] *** Failure: ', Result.ErrorMessageBrief);
  end;

  VarClear(Results);
  VarClear(Arguments);

  // Example output:
  //results[0].AttributeData: 4.187603E+21 {System.Single} @2019-11-09T14:05:46.268 @@2019-11-09T14:05:46.268; Good
  //results[1].AttributeData: -98 {System.Int16} @2019-11-09T14:05:46.268 @@2019-11-09T14:05:46.268; Good
  //results[2].AttributeData: [58] {38240, 11129, 64397, 22845, 30525, ...} {System.Int32[]} @2019-11-09T14:00:07.543 @@2019-11-09T14:05:46.268; Good
  //results[3].AttributeData: 1280120396 {System.Int32} @2019-11-09T14:00:07.590 @@2019-11-09T14:05:46.268; Good

end;

// This example shows how to read the attributes of 4 OPC-UA nodes specified by browse paths at once, and display the results.
//
// Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .
// OPC client and subscriber examples in PHP on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-PHP .
// Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own
// a commercial license in order to use Online Forums, and we reply to every post.

$BrowsePathParser = new COM("OpcLabs.EasyOpc.UA.Navigation.Parsing.UABrowsePathParser");
$BrowsePathParser->DefaultNamespaceUriString = "http://test.org/UA/Data/";

$ReadArguments1 = new COM("OpcLabs.EasyOpc.UA.OperationModel.UAReadArguments");
$ReadArguments1->EndpointDescriptor->UrlString = 
    //"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";
$ReadArguments1->NodeDescriptor->BrowsePath = $BrowsePathParser->Parse("[ObjectsFolder]/Data/Dynamic/Scalar/FloatValue");

$ReadArguments2 = new COM("OpcLabs.EasyOpc.UA.OperationModel.UAReadArguments");
$ReadArguments2->EndpointDescriptor->UrlString = 
    //"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";
$ReadArguments2->NodeDescriptor->BrowsePath = $BrowsePathParser->Parse("[ObjectsFolder]/Data/Dynamic/Scalar/SByteValue");

$ReadArguments3 = new COM("OpcLabs.EasyOpc.UA.OperationModel.UAReadArguments");
$ReadArguments3->EndpointDescriptor->UrlString = 
    //"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";
$ReadArguments3->NodeDescriptor->BrowsePath = $BrowsePathParser->Parse("[ObjectsFolder]/Data/Static/Array/UInt16Value");

$ReadArguments4 = new COM("OpcLabs.EasyOpc.UA.OperationModel.UAReadArguments");
$ReadArguments4->EndpointDescriptor->UrlString = 
    //"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";
$ReadArguments4->NodeDescriptor->BrowsePath = $BrowsePathParser->Parse("[ObjectsFolder]/Data/Static/UserScalar/Int32Value");

$arguments[0] = $ReadArguments1;
$arguments[1] = $ReadArguments2;
$arguments[2] = $ReadArguments3;
$arguments[3] = $ReadArguments4;

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

// Perform the operation
$results = $Client->ReadMultiple($arguments);

// Display results
for ($i = 0; $i < count($results); $i++)
{
    $attributeDataResult = $results[$i];
    if ($attributeDataResult->Succeeded)
        printf("results[d].AttributeDatas\n", $i, $attributeDataResult->AttributeData);
    else
        printf("results[d]: *** Failures\n", $i, $attributeDataResult->ErrorMessageBrief);
}

REM This example shows how to read the attributes of 4 OPC-UA nodes specified
REM by browse paths at once, and display the results.
REM
REM Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .
REM OPC client and subscriber examples in Visual Basic on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-VB .
REM Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own
REM a commercial license in order to use Online Forums, and we reply to every post.

Public Sub ReadMultiple_BrowsePath_Command_Click()
    OutputText = ""

    Dim BrowsePathParser As New UABrowsePathParser
    BrowsePathParser.DefaultNamespaceUriString = "http://test.org/UA/Data/"

    Dim readArguments1 As New UAReadArguments
    readArguments1.endpointDescriptor.UrlString = "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer"
    ' Note: Add error handling around the following statement if the browse path is not guaranteed to be syntactically valid.
    Set readArguments1.nodeDescriptor.browsePath = BrowsePathParser.Parse("[ObjectsFolder]/Data/Dynamic/Scalar/FloatValue")

    Dim ReadArguments2 As New UAReadArguments
    ReadArguments2.endpointDescriptor.UrlString = "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer"
    ' Note: Add error handling around the following statement if the browse path is not guaranteed to be syntactically valid.
    Set ReadArguments2.nodeDescriptor.browsePath = BrowsePathParser.Parse("[ObjectsFolder]/Data/Dynamic/Scalar/SByteValue")

    Dim ReadArguments3 As New UAReadArguments
    ReadArguments3.endpointDescriptor.UrlString = "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer"
    ' Note: Add error handling around the following statement if the browse path is not guaranteed to be syntactically valid.
    Set ReadArguments3.nodeDescriptor.browsePath = BrowsePathParser.Parse("[ObjectsFolder]/Data/Static/Array/UInt16Value")

    Dim ReadArguments4 As New UAReadArguments
    ReadArguments4.endpointDescriptor.UrlString = "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer"
    ' Note: Add error handling around the following statement if the browse path is not guaranteed to be syntactically valid.
    Set ReadArguments4.nodeDescriptor.browsePath = BrowsePathParser.Parse("[ObjectsFolder]/Data/Static/UserScalar/Int32Value")

    Dim arguments(3) As Variant
    Set arguments(0) = readArguments1
    Set arguments(1) = ReadArguments2
    Set arguments(2) = ReadArguments3
    Set arguments(3) = ReadArguments4

    ' Instantiate the client object
    Dim Client As New EasyUAClient

    ' Obtain values. By default, the Value attributes of the nodes will be read.
    Dim results() As Variant
    results = Client.ReadMultiple(arguments)

    ' Display results
    Dim i: For i = LBound(results) To UBound(results)
        Dim Result As UAAttributeDataResult: Set Result = results(i)
        If Result.Succeeded Then
            OutputText = OutputText & "results(" & i & ").AttributeData: " & Result.AttributeData & vbCrLf
        Else
            OutputText = OutputText & "results(" & i & ") *** Failure: " & Result.ErrorMessageBrief & vbCrLf
        End If
    Next
    
    ' Example output:
    'results(0).AttributeData: 4.187603E+21 {System.Single} @2019-11-09T14:05:46.268 @@2019-11-09T14:05:46.268; Good
    'results(1).AttributeData: -98 {System.Int16} @2019-11-09T14:05:46.268 @@2019-11-09T14:05:46.268; Good
    'results(2).AttributeData: [58] {38240, 11129, 64397, 22845, 30525, ...} {System.Int32[]} @2019-11-09T14:00:07.543 @@2019-11-09T14:05:46.268; Good
    'results(3).AttributeData: 1280120396 {System.Int32} @2019-11-09T14:00:07.590 @@2019-11-09T14:05:46.268; Good
End Sub

Rem This example shows how to read the attributes of 4 OPC-UA nodes specified by browse paths at once, and display the 
Rem results.
Rem
Rem Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .
Rem OPC client and subscriber examples in VBScript on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-VBScript .
Rem Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own
Rem a commercial license in order to use Online Forums, and we reply to every post.

Option Explicit

Dim BrowsePathParser: Set BrowsePathParser = CreateObject("OpcLabs.EasyOpc.UA.Navigation.Parsing.UABrowsePathParser")
BrowsePathParser.DefaultNamespaceUriString = "http://test.org/UA/Data/"

Dim ReadArguments1: Set ReadArguments1 = CreateObject("OpcLabs.EasyOpc.UA.OperationModel.UAReadArguments")
ReadArguments1.EndpointDescriptor.UrlString = "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer"
' Note: Add error handling around the following statement if the browse path is not guaranteed to be syntactically valid.
ReadArguments1.NodeDescriptor.BrowsePath = BrowsePathParser.Parse("[ObjectsFolder]/Data/Dynamic/Scalar/FloatValue")

Dim ReadArguments2: Set ReadArguments2 = CreateObject("OpcLabs.EasyOpc.UA.OperationModel.UAReadArguments")
ReadArguments2.EndpointDescriptor.UrlString = "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer"
' Note: Add error handling around the following statement if the browse path is not guaranteed to be syntactically valid.
ReadArguments2.NodeDescriptor.BrowsePath = BrowsePathParser.Parse("[ObjectsFolder]/Data/Dynamic/Scalar/SByteValue")

Dim ReadArguments3: Set ReadArguments3 = CreateObject("OpcLabs.EasyOpc.UA.OperationModel.UAReadArguments")
ReadArguments3.EndpointDescriptor.UrlString = "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer"
' Note: Add error handling around the following statement if the browse path is not guaranteed to be syntactically valid.
ReadArguments3.NodeDescriptor.BrowsePath = BrowsePathParser.Parse("[ObjectsFolder]/Data/Static/Array/UInt16Value")

Dim ReadArguments4: Set ReadArguments4 = CreateObject("OpcLabs.EasyOpc.UA.OperationModel.UAReadArguments")
ReadArguments4.EndpointDescriptor.UrlString = "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer"
' Note: Add error handling around the following statement if the browse path is not guaranteed to be syntactically valid.
ReadArguments4.NodeDescriptor.BrowsePath = BrowsePathParser.Parse("[ObjectsFolder]/Data/Static/UserScalar/Int32Value")

Dim arguments(3)
Set arguments(0) = ReadArguments1
Set arguments(1) = ReadArguments2
Set arguments(2) = ReadArguments3
Set arguments(3) = ReadArguments4

' Instantiate the client object
Dim Client: Set Client = CreateObject("OpcLabs.EasyOpc.UA.EasyUAClient")

' Perform the operation
Dim results: results = Client.ReadMultiple(arguments)

' Display results
Dim i: For i = LBound(results) To UBound(results)
    Dim AttributeDataResult: Set AttributeDataResult = results(i)
    If AttributeDataResult.Succeeded Then
        WScript.Echo "results[" & i & "].AttributeData: " & AttributeDataResult.AttributeData
    Else
        WScript.Echo "results[" & i & "] *** Failure: " & AttributeDataResult.ErrorMessageBrief
    End If
Next

' Example output:
'results[0].AttributeData: 4.187603E+21 {System.Single} @2019-11-09T14:05:46.268 @@2019-11-09T14:05:46.268; Good
'results[1].AttributeData: -98 {System.Int16} @2019-11-09T14:05:46.268 @@2019-11-09T14:05:46.268; Good
'results[2].AttributeData: [58] {38240, 11129, 64397, 22845, 30525, ...} {System.Int32[]} @2019-11-09T14:00:07.543 @@2019-11-09T14:05:46.268; Good
'results[3].AttributeData: 1280120396 {System.Int32} @2019-11-09T14:00:07.590 @@2019-11-09T14:05:46.268; Good

<!-- This example shows how to read the attributes of 4 OPC-UA nodes at once, and display the results. -->
<!---->
<!-- Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .-->
<!-- OPC client and subscriber examples in PHP on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-PHP .-->
<!-- Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own-->
<!-- a commercial license in order to use Online Forums, and we reply to every post.-->
<html>
<body>
<?php

    $ReadArguments1 = new COM("OpcLabs.EasyOpc.UA.OperationModel.UAReadArguments");
    $ReadArguments1->EndpointDescriptor->UrlString = 
        //"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";
    $ReadArguments1->NodeDescriptor->NodeId->ExpandedText = "nsu=http://test.org/UA/Data/ ;i=10853";

    $ReadArguments2 = new COM("OpcLabs.EasyOpc.UA.OperationModel.UAReadArguments");
    $ReadArguments2->EndpointDescriptor->UrlString = 
        //"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";
    $ReadArguments2->NodeDescriptor->NodeId->ExpandedText = "nsu=http://test.org/UA/Data/ ;i=10845";

    $ReadArguments3 = new COM("OpcLabs.EasyOpc.UA.OperationModel.UAReadArguments");
    $ReadArguments3->EndpointDescriptor->UrlString = 
        //"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";
    $ReadArguments3->NodeDescriptor->NodeId->ExpandedText = "nsu=http://test.org/UA/Data/ ;i=10304";

    $ReadArguments4 = new COM("OpcLabs.EasyOpc.UA.OperationModel.UAReadArguments");
    $ReadArguments4->EndpointDescriptor->UrlString = 
        //"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";
    $ReadArguments4->NodeDescriptor->NodeId->ExpandedText = "nsu=http://test.org/UA/Data/ ;i=10389";

    $arguments[0] = $ReadArguments1;
    $arguments[1] = $ReadArguments2;
    $arguments[2] = $ReadArguments3;
    $arguments[3] = $ReadArguments4;

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

    // Perform the operation
    $results = $Client->ReadMultiple($arguments);

    // Display results
    for ($i = 0; $i < count($results); $i++)
    {
        printf("results[d].AttributeDatas<br>", $i, $results[$i]->AttributeData);
    }

?>
</body>
</html>

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

_EasyUAClient Interface
_EasyUAClient Members
SubscribeMultipleMonitoredItems Method
WriteMultiple Method

Documentation Home, Send Feedback. Resources: Knowledge Base, Product Downloads. Technical support: Online Forums, FAQ.

Missing some example? Ask us for it on our Online Forums! You do not have to own a commercial license in order to use Online Forums, and we reply to every post.