CallMultipleMethods Method (

Calls multiple methods, using array of argument objects as an input.

Syntax

Visual Basic
C#
C++/CLI

'Declaration
 
<ElementsNotNullAttribute()>
<NotNullAttribute()>
Function CallMultipleMethods( _
   ByVal callArgumentsArray As Object _
) As Object()

'Usage
 
Dim instance As _EasyUAClient
Dim callArgumentsArray As Object
Dim value() As Object
 
value = instance.CallMultipleMethods(callArgumentsArray)

[ElementsNotNull()]
[NotNull()]
object[] CallMultipleMethods( 
   object callArgumentsArray
)

[ElementsNotNull()]
[NotNull()]
array<Object^>^ CallMultipleMethods( 
   Object^ callArgumentsArray
)

Parameters

callArgumentsArray: Array of OpcLabs.EasyOpc.UA.OperationModel.UACallArguments. Specifies which methods to call in an OPC-UA server, and their input arguments.

Return Value

Array of OpcLabs.BaseLib.OperationModel.ValueArrayResult. Array of output arguments from the method call. The number of arguments and their types are given by the method.

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

If you want to call methods that are defined in the OPC UA specifications or OPC UA companion specifications, consider first whether extension methods or specialized client objects exist for the purpose, because using them is much easier. For example, in order to call methods provided by OPC UA Global Discovery Server (GDS), you should rather use the OpcLabs.EasyOpc.UA.Gds.EasyUAGlobalDiscoveryClientCore or the OpcLabs.EasyOpc.UA.Gds.EasyUACertificateManagementClientCore object, or use the methods provided by the OpcLabs.EasyOpc.UA.Application.IEasyUAClientServerApplication service.

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.

Example

.NET

// This example shows how to call multiple methods, and pass arguments to and
// from them.

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

namespace UADocExamples._EasyUAClient
{
    class CallMultipleMethods
    {
        public static void Main1()
        {

            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=10755";

            object[] inputs1 =
            {
                false, 
                1, 
                2, 
                3, 
                4, 
                5, 
                6, 
                7, 
                8, 
                9, 
                10
            };

            TypeCode[] typeCodes1 =
            {
                TypeCode.Boolean,
                TypeCode.SByte,
                TypeCode.Byte,
                TypeCode.Int16,
                TypeCode.UInt16,
                TypeCode.Int32,
                TypeCode.UInt32,
                TypeCode.Int64,
                TypeCode.UInt64,
                TypeCode.Single,
                TypeCode.Double
            };

            object[] inputs2 =
            {
                false, 
                1, 
                2, 
                3, 
                4, 
                5, 
                6, 
                7, 
                8, 
                9, 
                10,
                "eleven"
            };

            TypeCode[] typeCodes2 =
            {
                TypeCode.Boolean,
                TypeCode.SByte,
                TypeCode.Byte,
                TypeCode.Int16,
                TypeCode.UInt16,
                TypeCode.Int32,
                TypeCode.UInt32,
                TypeCode.Int64,
                TypeCode.UInt64,
                TypeCode.Single,
                TypeCode.Double,
                TypeCode.String
            };

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

            // Perform the operation.
            ValueArrayResult[] results = client.CallMultipleMethods(new[]
            {
                new UACallArguments(endpointDescriptor, nodeDescriptor, 
                    "nsu=http://test.org/UA/Data/ ;i=10756", inputs1, typeCodes1),
                new UACallArguments(endpointDescriptor, nodeDescriptor, 
                    "nsu=http://test.org/UA/Data/ ;i=10774", inputs2, typeCodes2)
            });

            // Display results
            for (int i = 0; i < results.Length; i++)
            {
                Console.WriteLine();
                Console.WriteLine($"results[{i}]:");

                ValueArrayResult result = results[i];
                if (result.Succeeded)
                {
                    object[] outputs = result.ValueArray;
                    Debug.Assert(outputs != null);

                    for (int j = 0; j < outputs.Length; j++)
                        Console.WriteLine($"    outputs[{j}]: {outputs[j]}");
                }
                else
                    Console.WriteLine($"*** Failure: {result.ErrorMessageBrief}");
            }

            // Example output:
            //results[0]:
            //    outputs[0]: False
            //    outputs[1]: 1
            //    outputs[2]: 2
            //    outputs[3]: 3
            //    outputs[4]: 4
            //    outputs[5]: 5
            //    outputs[6]: 6
            //    outputs[7]: 7
            //    outputs[8]: 8
            //    outputs[9]: 9
            //    outputs[10]: 10

            //results[1]:
            //    outputs[0]: False
            //    outputs[1]: 1
            //    outputs[2]: 2
            //    outputs[3]: 3
            //    outputs[4]: 4
            //    outputs[5]: 5
            //    outputs[6]: 6
            //    outputs[7]: 7
            //    outputs[8]: 8
            //    outputs[9]: 9
            //    outputs[10]: 10
            //    outputs[11]: eleven
        }
    }
}

# This example shows how to call multiple methods, and pass arguments to and
# from them.

#requires -Version 5.1
using namespace OpcLabs.BaseLib.OperationModel
using namespace OpcLabs.EasyOpc.UA
using namespace OpcLabs.EasyOpc.UA.OperationModel

# The path below assumes that the current directory is [ProductDir]/Examples-NET/PowerShell/Windows .
Add-Type -Path "../../../Components/Opclabs.QuickOpc/net472/OpcLabs.EasyOpcUA.dll"
Add-Type -Path "../../../Components/Opclabs.QuickOpc/net472/OpcLabs.EasyOpcUAComponents.dll"

[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/"
$nodeDescriptor = New-Object UANodeDescriptor("nsu=http://test.org/UA/Data/ ;i=10755")

$inputs1 = @(
    $false,
    1, 
    2, 
    3, 
    4, 
    5, 
    6, 
    7, 
    8, 
    9, 
    10)

$typeCodes1 = @(
    [TypeCode]::Boolean,
    [TypeCode]::SByte,
    [TypeCode]::Byte,
    [TypeCode]::Int16,
    [TypeCode]::UInt16,
    [TypeCode]::Int32,
    [TypeCode]::UInt32,
    [TypeCode]::Int64,
    [TypeCode]::UInt64,
    [TypeCode]::Single,
    [TypeCode]::Double)


$inputs2 = @(
    $false, 
    1, 
    2, 
    3, 
    4, 
    5, 
    6, 
    7, 
    8, 
    9, 
    10,
    "eleven")

$typeCodes2 = @(
    [TypeCode]::Boolean,
    [TypeCode]::SByte,
    [TypeCode]::Byte,
    [TypeCode]::Int16,
    [TypeCode]::UInt16,
    [TypeCode]::Int32,
    [TypeCode]::UInt32,
    [TypeCode]::Int64,
    [TypeCode]::UInt64,
    [TypeCode]::Single,
    [TypeCode]::Double,
    [TypeCode]::String)

# Instantiate the client object.
$client = New-Object EasyUAClient

# Perform the operation.
$results = $client.CallMultipleMethods(@(
    (New-Object UACallArguments($endpointDescriptor, $nodeDescriptor, 
        "nsu=http://test.org/UA/Data/ ;i=10756", $inputs1, $typeCodes1)),
    (New-Object UACallArguments($endpointDescriptor, $nodeDescriptor, 
        "nsu=http://test.org/UA/Data/ ;i=10774", $inputs2, $typeCodes2))
    ))

# Display results
for ($i = 0; $i -lt $results.Length; $i++) {
    Write-Host
    Write-Host "results[$($i)]:"

    $result = $results[$i]
    if ($result.Succeeded) {
        $outputs = $result.ValueArray
        for ($j = 0; $j -lt $outputs.Length; $j++) {
            Write-Host "    outputs[$($j)]: $($outputs[$j])"
        }
    }
    else {
        Write-Host "*** Failure: $($vtqResult.ErrorMessageBrief)"
    }


# Example output:
#
#results[0]:
#    outputs[0]: False
#    outputs[1]: 1
#    outputs[2]: 2
#    outputs[3]: 3
#    outputs[4]: 4
#    outputs[5]: 5
#    outputs[6]: 6
#    outputs[7]: 7
#    outputs[8]: 8
#    outputs[9]: 9
#    outputs[10]: 10

#results[1]:
#    outputs[0]: False
#    outputs[1]: 1
#    outputs[2]: 2
#    outputs[3]: 3
#    outputs[4]: 4
#    outputs[5]: 5
#    outputs[6]: 6
#    outputs[7]: 7
#    outputs[8]: 8
#    outputs[9]: 9
#    outputs[10]: 10
#    outputs[11]: eleven
}

# This example shows how to call multiple methods, and pass arguments to and
# from them.

# 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/'
nodeDescriptor = UANodeDescriptor('nsu=http://test.org/UA/Data/ ;i=10755')

#
inputs1 = [False, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
typeCodes1 = [
    TypeCode.Boolean,
    TypeCode.SByte,
    TypeCode.Byte,
    TypeCode.Int16,
    TypeCode.UInt16,
    TypeCode.Int32,
    TypeCode.UInt32,
    TypeCode.Int64,
    TypeCode.UInt64,
    TypeCode.Single,
    TypeCode.Double,
    ]

inputs2 = [False, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 'eleven']
typeCodes2 = [
    TypeCode.Boolean,
    TypeCode.SByte,
    TypeCode.Byte,
    TypeCode.Int16,
    TypeCode.UInt16,
    TypeCode.Int32,
    TypeCode.UInt32,
    TypeCode.Int64,
    TypeCode.UInt64,
    TypeCode.Single,
    TypeCode.Double,
    TypeCode.String,
    ]

# Instantiate the client object.
client = EasyUAClient()

# Perform the operation.
try:
    valueArrayResultArray = client.CallMultipleMethods([
        UACallArguments(endpointDescriptor, nodeDescriptor,
                        UANodeDescriptor('nsu=http://test.org/UA/Data/ ;i=10756'), inputs1, typeCodes1),
        UACallArguments(endpointDescriptor, nodeDescriptor,
                        UANodeDescriptor('nsu=http://test.org/UA/Data/ ;i=10774'), inputs2, typeCodes2),
        ])
except UAException as uaException:
    print('*** Failure: ' + uaException.GetBaseException().Message)
    exit()

# Display results.
for i, valueArrayResult in enumerate(valueArrayResultArray):
    print()
    print('valueArrayResultArray[', i, ']:', sep='')
    if valueArrayResult.Succeeded:
        assert valueArrayResult.ValueArray is not None
        for j, outputValueArray in enumerate(valueArrayResult.ValueArray):
            print('    valueArray[', j, ']: ', outputValueArray, sep='')
    else:
        print('*** Failure: ', valueArrayResult.ErrorMessageBrief, sep='')

print()
print('Finished.')

' This example shows how to call multiple methods, and pass arguments to and
' from them.

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

Namespace _EasyUAClient
    Friend Class CallMultipleMethods
        Public Shared Sub Main1()

            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/"
            Dim nodeDescriptor As UANodeDescriptor = "nsu=http://test.org/UA/Data/ ;i=10755"

            Dim inputs1() As Object =
            { _
                False,
                1,
                2,
                3,
                4,
                5,
                6,
                7,
                8,
                9,
                10
            }

            Dim typeCodes1() As TypeCode =
            { _
                TypeCode.Boolean,
                TypeCode.SByte,
                TypeCode.Byte,
                TypeCode.Int16,
                TypeCode.UInt16,
                TypeCode.Int32,
                TypeCode.UInt32,
                TypeCode.Int64,
                TypeCode.UInt64,
                TypeCode.Single,
                TypeCode.Double
            }

            Dim inputs2() As Object =
            { _
                False,
                1,
                2,
                3,
                4,
                5,
                6,
                7,
                8,
                9,
                10,
                "eleven"
            }

            Dim typeCodes2() As TypeCode =
            { _
                TypeCode.Boolean,
                TypeCode.SByte,
                TypeCode.Byte,
                TypeCode.Int16,
                TypeCode.UInt16,
                TypeCode.Int32,
                TypeCode.UInt32,
                TypeCode.Int64,
                TypeCode.UInt64,
                TypeCode.Single,
                TypeCode.Double,
                TypeCode.String
            }

            ' Instantiate the client object
            Dim client = New EasyUAClient()

            ' Perform the operation
            Dim results() As ValueArrayResult = client.CallMultipleMethods(New UACallArguments() _
    { _
        New UACallArguments(endpointDescriptor, nodeDescriptor, _
            "nsu=http://test.org/UA/Data/ ;i=10756", inputs1, typeCodes1), _
        New UACallArguments(endpointDescriptor, nodeDescriptor, _
            "nsu=http://test.org/UA/Data/ ;i=10774", inputs2, typeCodes2) _
    } _
            )

            ' Display results
            For i As Integer = 0 To results.Length - 1
                Console.WriteLine()
                Console.WriteLine("results[{0}]:", i)

                Dim result As ValueArrayResult = results(i)
                If result.Succeeded Then
                    Dim outputs As Object() = result.ValueArray
                    Debug.Assert(outputs IsNot Nothing)

                    For j As Integer = 0 To outputs.Length - 1
                        Console.WriteLine("    outputs[{0}]: {1}", j, outputs(j))
                    Next j
                Else
                    Console.WriteLine("*** Failure: {0}", result.ErrorMessageBrief)
                End If
            Next i

            ' Example output:
            'outputs[0]: False
            'outputs[1]: 1
            'outputs[2]: 2
            'outputs[3]: 3
            'outputs[4]: 4
            'outputs[5]: 5
            'outputs[6]: 6
            'outputs[7]: 7
            'outputs[8]: 8
            'outputs[9]: 9
            'outputs[10]: 10       

            'results[1]:
            'outputs[0]: False
            'outputs[1]: 1
            'outputs[2]: 2
            'outputs[3]: 3
            'outputs[4]: 4
            'outputs[5]: 5
            'outputs[6]: 6
            'outputs[7]: 7
            'outputs[8]: 8
            'outputs[9]: 9
            'outputs[10]: 10
            'outputs[11]: eleven
        End Sub
    End Class
End Namespace

C++
Free Pascal
Object Pascal
Visual Basic (VB 6.0)
VBScript

// This example shows how to call multiple methods, and pass arguments to and from them.

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

namespace _EasyUAClient
{
    void CallMultipleMethods::Main()
    {
        // Initialize the COM library
        CoInitializeEx(NULL, COINIT_MULTITHREADED);
        {
            CComSafeArray<VARIANT> inputs1(11);
            inputs1.SetAt(0, _variant_t(false));
            inputs1.SetAt(1, _variant_t(1));
            inputs1.SetAt(2, _variant_t(2));
            inputs1.SetAt(3, _variant_t(3));
            inputs1.SetAt(4, _variant_t(4));
            inputs1.SetAt(5, _variant_t(5));
            inputs1.SetAt(6, _variant_t(6));
            inputs1.SetAt(7, _variant_t(7));
            inputs1.SetAt(8, _variant_t(8));
            inputs1.SetAt(9, _variant_t(9));
            inputs1.SetAt(10, _variant_t(10));

            CComSafeArray<VARIANT> typeCodes1(11);
            typeCodes1.SetAt(0, _variant_t(TypeCode_Boolean));
            typeCodes1.SetAt(1, _variant_t(TypeCode_SByte));
            typeCodes1.SetAt(2, _variant_t(TypeCode_Byte));
            typeCodes1.SetAt(3, _variant_t(TypeCode_Int16));
            typeCodes1.SetAt(4, _variant_t(TypeCode_UInt16));
            typeCodes1.SetAt(5, _variant_t(TypeCode_Int32));
            typeCodes1.SetAt(6, _variant_t(TypeCode_UInt32));
            typeCodes1.SetAt(7, _variant_t(TypeCode_Int64));
            typeCodes1.SetAt(8, _variant_t(TypeCode_UInt64));
            typeCodes1.SetAt(9, _variant_t(TypeCode_Single));
            typeCodes1.SetAt(10, _variant_t(TypeCode_Double));
            CComVariant vTypeCodes1(typeCodes1);

            _UACallArgumentsPtr CallArguments1Ptr(__uuidof(UACallArguments));
            CallArguments1Ptr->EndpointDescriptor->UrlString = 
                //L"http://opcua.demo-this.com:51211/UA/SampleServer";
                L"opc.tcp://opcua.demo-this.com:51210/UA/SampleServer";
                CallArguments1Ptr->NodeDescriptor->NodeId->ExpandedText = L"nsu=http://test.org/UA/Data/ ;i=10755";
            CallArguments1Ptr->MethodNodeDescriptor->NodeId->ExpandedText = L"nsu=http://test.org/UA/Data/ ;i=10756";
            CallArguments1Ptr->InputArguments = inputs1;
            CallArguments1Ptr->InputTypeCodes = vTypeCodes1;

            CComSafeArray<VARIANT> inputs2(12);
            inputs2.SetAt(0, _variant_t(false));
            inputs2.SetAt(1, _variant_t(1));
            inputs2.SetAt(2, _variant_t(2));
            inputs2.SetAt(3, _variant_t(3));
            inputs2.SetAt(4, _variant_t(4));
            inputs2.SetAt(5, _variant_t(5));
            inputs2.SetAt(6, _variant_t(6));
            inputs2.SetAt(7, _variant_t(7));
            inputs2.SetAt(8, _variant_t(8));
            inputs2.SetAt(9, _variant_t(9));
            inputs2.SetAt(10, _variant_t(10));
            inputs2.SetAt(11, _variant_t(L"eleven"));

            CComSafeArray<VARIANT> typeCodes2(12);
            typeCodes2.SetAt(0, _variant_t(TypeCode_Boolean));
            typeCodes2.SetAt(1, _variant_t(TypeCode_SByte));
            typeCodes2.SetAt(2, _variant_t(TypeCode_Byte));
            typeCodes2.SetAt(3, _variant_t(TypeCode_Int16));
            typeCodes2.SetAt(4, _variant_t(TypeCode_UInt16));
            typeCodes2.SetAt(5, _variant_t(TypeCode_Int32));
            typeCodes2.SetAt(6, _variant_t(TypeCode_UInt32));
            typeCodes2.SetAt(7, _variant_t(TypeCode_Int64));
            typeCodes2.SetAt(8, _variant_t(TypeCode_UInt64));
            typeCodes2.SetAt(9, _variant_t(TypeCode_Single));
            typeCodes2.SetAt(10, _variant_t(TypeCode_Double));
            typeCodes2.SetAt(11, _variant_t(TypeCode_String));
            CComVariant vTypeCodes2(typeCodes2);

            _UACallArgumentsPtr CallArguments2Ptr(__uuidof(UACallArguments));
            CallArguments2Ptr->EndpointDescriptor->UrlString = 
                //L"http://opcua.demo-this.com:51211/UA/SampleServer";
                L"opc.tcp://opcua.demo-this.com:51210/UA/SampleServer";
            CallArguments2Ptr->NodeDescriptor->NodeId->ExpandedText = L"nsu=http://test.org/UA/Data/ ;i=10755";
            CallArguments2Ptr->MethodNodeDescriptor->NodeId->ExpandedText = L"nsu=http://test.org/UA/Data/ ;i=10774";
            CallArguments2Ptr->InputArguments = inputs2;
            CallArguments2Ptr->InputTypeCodes = vTypeCodes2;

            CComSafeArray<VARIANT> arguments(2);
            arguments.SetAt(0, _variant_t((IDispatch*)CallArguments1Ptr));
            arguments.SetAt(1, _variant_t((IDispatch*)CallArguments2Ptr));
            CComVariant vArguments(arguments);

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

            // Perform the operation
            CComSafeArray<VARIANT> results;
            results.Attach(ClientPtr->CallMultipleMethods(&vArguments));
    
            // Display results
            for (int i = results.GetLowerBound(); i <= results.GetUpperBound(); i++)
            {
                _tprintf(_T("\n"));
                _tprintf(_T("results(%d):\n"), i);
                _ValueArrayResultPtr ResultPtr = results[i];

                if (ResultPtr->Exception == NULL)
                {
                    CComVariant valueArray(ResultPtr->ValueArray);
                    CComSafeArray<VARIANT> outputs(valueArray.parray);
                    for (int j = outputs.GetLowerBound(); j <= outputs.GetUpperBound(); j++)
                    {
                        _variant_t output(outputs[j]);
                        _variant_t vString;
                        vString.ChangeType(VT_BSTR, &output);
                        _tprintf(_T("    outputs(d)s\n"), i, (LPCTSTR)CW2CT((_bstr_t)vString));
                    }
                }
                else
                    _tprintf(_T("*** Error: %s\n"), (LPCTSTR)CW2CT(ResultPtr->Exception->ToString));
            }
        }
         // Release all interface pointers BEFORE calling CoUninitialize()
        CoUninitialize();
    }
}

// This example shows how to call multiple methods, and pass arguments to and
// from them.

class procedure CallMultipleMethods.Main;
var
  Arguments: OleVariant;
  CallArguments1, CallArguments2: _UACallArguments;
  Client: EasyUAClient;
  I, J: Cardinal;
  Inputs1, Inputs2: OleVariant;
  Outputs: OleVariant;
  Result: _ValueArrayResult;
  Results: OleVariant;
  TypeCodes1, TypeCodes2: OleVariant;
begin
  Inputs1 := VarArrayCreate([0, 10], varVariant);
  Inputs1[0] := False;
  Inputs1[1] := 1;
  Inputs1[2] := 2;
  Inputs1[3] := 3;
  Inputs1[4] := 4;
  Inputs1[5] := 5;
  Inputs1[6] := 6;
  Inputs1[7] := 7;
  Inputs1[8] := 8;
  Inputs1[9] := 9;
  Inputs1[10] := 10;

  TypeCodes1 := VarArrayCreate([0, 10], varVariant);
  TypeCodes1[0] := TypeCode_Boolean;
  TypeCodes1[1] := TypeCode_SByte;
  TypeCodes1[2] := TypeCode_Byte;
  TypeCodes1[3] := TypeCode_Int16;
  TypeCodes1[4] := TypeCode_UInt16;
  TypeCodes1[5] := TypeCode_Int32;
  TypeCodes1[6] := TypeCode_UInt32;
  TypeCodes1[7] := TypeCode_Int64;
  TypeCodes1[8] := TypeCode_UInt64;
  TypeCodes1[9] := TypeCode_Single;
  TypeCodes1[10] := TypeCode_Double;

  CallArguments1 := CoUACallArguments.Create;
  CallArguments1.EndpointDescriptor.UrlString := 
    //'http://opcua.demo-this.com:51211/UA/SampleServer';
    'opc.tcp://opcua.demo-this.com:51210/UA/SampleServer';
  CallArguments1.NodeDescriptor.NodeId.ExpandedText := 'nsu=http://test.org/UA/Data/ ;i=10755';
  CallArguments1.MethodNodeDescriptor.NodeId.ExpandedText := 'nsu=http://test.org/UA/Data/ ;i=10756';
  CallArguments1.InputArguments := PSafeArray(TVarData(Inputs1).VArray);
  CallArguments1.InputTypeCodes := PSafeArray(TVarData(TypeCodes1).VArray);

  Inputs2 := VarArrayCreate([0, 11], varVariant);
  Inputs2[0] := False;
  Inputs2[1] := 1;
  Inputs2[2] := 2;
  Inputs2[3] := 3;
  Inputs2[4] := 4;
  Inputs2[5] := 5;
  Inputs2[6] := 6;
  Inputs2[7] := 7;
  Inputs2[8] := 8;
  Inputs2[9] := 9;
  Inputs2[10] := 10;
  Inputs2[11] := 'eleven';

  TypeCodes2 := VarArrayCreate([0, 11], varVariant);
  TypeCodes2[0] := TypeCode_Boolean;
  TypeCodes2[1] := TypeCode_SByte;
  TypeCodes2[2] := TypeCode_Byte;
  TypeCodes2[3] := TypeCode_Int16;
  TypeCodes2[4] := TypeCode_UInt16;
  TypeCodes2[5] := TypeCode_Int32;
  TypeCodes2[6] := TypeCode_UInt32;
  TypeCodes2[7] := TypeCode_Int64;
  TypeCodes2[8] := TypeCode_UInt64;
  TypeCodes2[9] := TypeCode_Single;
  TypeCodes2[10] := TypeCode_Double;
  TypeCodes2[11] := TypeCode_String;

  CallArguments2 := CoUACallArguments.Create;
  CallArguments2.EndpointDescriptor.UrlString := 
    //'http://opcua.demo-this.com:51211/UA/SampleServer';
    'opc.tcp://opcua.demo-this.com:51210/UA/SampleServer';
  CallArguments2.NodeDescriptor.NodeId.ExpandedText := 'nsu=http://test.org/UA/Data/ ;i=10755';
  CallArguments2.MethodNodeDescriptor.NodeId.ExpandedText := 'nsu=http://test.org/UA/Data/ ;i=10774';
  CallArguments2.InputArguments := PSafeArray(TVarData(Inputs2).VArray);
  CallArguments2.InputTypeCodes := PSafeArray(TVarData(TypeCodes2).VArray);

  Arguments := VarArrayCreate([0, 1], varVariant);
  Arguments[0] := CallArguments1;
  Arguments[1] := CallArguments2;

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

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

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

    if Result.Exception = nil then
      begin
        TVarData(Outputs).VType := varArray or varVariant;
        TVarData(Outputs).VArray := PVarArray(Result.ValueArray);
        for J := VarArrayLowBound(Outputs, 1) to VarArrayHighBound(Outputs, 1) do
          try
            WriteLn('    ', 'outputs(', J, '): ', Outputs[J]);
          except
            on EVariantError do WriteLn('*** Error displaying the value');
          end;
      end
    else
      WriteLn('*** Error: ', Result.Exception.ToString);
  end;
end;

// This example shows how to call multiple methods, and pass arguments to and
// from them.

class procedure CallMultipleMethods.Main;
var
  Arguments: OleVariant;
  CallArguments1, CallArguments2: _UACallArguments;
  Client: OpcLabs_EasyOpcUA_TLB._EasyUAClient;
  I, J: Cardinal;
  Inputs1, Inputs2: OleVariant;
  Outputs: OleVariant;
  Result: _ValueArrayResult;
  Results: OleVariant;
  TypeCodes1, TypeCodes2: OleVariant;
begin
  Inputs1 := VarArrayCreate([0, 10], varVariant);
  Inputs1[0] := False;
  Inputs1[1] := 1;
  Inputs1[2] := 2;
  Inputs1[3] := 3;
  Inputs1[4] := 4;
  Inputs1[5] := 5;
  Inputs1[6] := 6;
  Inputs1[7] := 7;
  Inputs1[8] := 8;
  Inputs1[9] := 9;
  Inputs1[10] := 10;

  TypeCodes1 := VarArrayCreate([0, 10], varVariant);
  TypeCodes1[0] := TypeCode_Boolean;
  TypeCodes1[1] := TypeCode_SByte;
  TypeCodes1[2] := TypeCode_Byte;
  TypeCodes1[3] := TypeCode_Int16;
  TypeCodes1[4] := TypeCode_UInt16;
  TypeCodes1[5] := TypeCode_Int32;
  TypeCodes1[6] := TypeCode_UInt32;
  TypeCodes1[7] := TypeCode_Int64;
  TypeCodes1[8] := TypeCode_UInt64;
  TypeCodes1[9] := TypeCode_Single;
  TypeCodes1[10] := TypeCode_Double;

  CallArguments1 := CoUACallArguments.Create;
  CallArguments1.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';
  CallArguments1.NodeDescriptor.NodeId.ExpandedText := 'nsu=http://test.org/UA/Data/ ;i=10755';
  CallArguments1.MethodNodeDescriptor.NodeId.ExpandedText := 'nsu=http://test.org/UA/Data/ ;i=10756';
  CallArguments1.InputArguments := PSafeArray(TVarData(Inputs1).VArray);
  CallArguments1.InputTypeCodes := TypeCodes1;

  Inputs2 := VarArrayCreate([0, 11], varVariant);
  Inputs2[0] := False;
  Inputs2[1] := 1;
  Inputs2[2] := 2;
  Inputs2[3] := 3;
  Inputs2[4] := 4;
  Inputs2[5] := 5;
  Inputs2[6] := 6;
  Inputs2[7] := 7;
  Inputs2[8] := 8;
  Inputs2[9] := 9;
  Inputs2[10] := 10;
  Inputs2[11] := 'eleven';

  TypeCodes2 := VarArrayCreate([0, 11], varVariant);
  TypeCodes2[0] := TypeCode_Boolean;
  TypeCodes2[1] := TypeCode_SByte;
  TypeCodes2[2] := TypeCode_Byte;
  TypeCodes2[3] := TypeCode_Int16;
  TypeCodes2[4] := TypeCode_UInt16;
  TypeCodes2[5] := TypeCode_Int32;
  TypeCodes2[6] := TypeCode_UInt32;
  TypeCodes2[7] := TypeCode_Int64;
  TypeCodes2[8] := TypeCode_UInt64;
  TypeCodes2[9] := TypeCode_Single;
  TypeCodes2[10] := TypeCode_Double;
  TypeCodes2[11] := TypeCode_String;

  CallArguments2 := CoUACallArguments.Create;
  CallArguments2.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';
  CallArguments2.NodeDescriptor.NodeId.ExpandedText := 'nsu=http://test.org/UA/Data/ ;i=10755';
  CallArguments2.MethodNodeDescriptor.NodeId.ExpandedText := 'nsu=http://test.org/UA/Data/ ;i=10774';
  CallArguments2.InputArguments := PSafeArray(TVarData(Inputs2).VArray);
  CallArguments2.InputTypeCodes := TypeCodes2;

  Arguments := VarArrayCreate([0, 1], varVariant);
  Arguments[0] := CallArguments1;
  Arguments[1] := CallArguments2;

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

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

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

    if Result.Exception = nil then
      begin
        Outputs := Result.ValueArray;
        for J := VarArrayLowBound(Outputs, 1) to VarArrayHighBound(Outputs, 1) do
          WriteLn('    ', 'outputs(', J, '): ', Outputs[J]);
      end
    else
      WriteLn('*** Failure: ', Result.Exception.ToString);
  end;

  VarClear(Results);
  VarClear(TypeCodes2);
  VarClear(TypeCodes1);
  VarClear(Arguments);
end;

Rem This example shows how to call multiple methods, and pass arguments to and from them.

Public Sub CallMultipleMethods_Main_Command_Click()
    OutputText = ""

    Dim inputs1(10)
    inputs1(0) = False
    inputs1(1) = 1
    inputs1(2) = 2
    inputs1(3) = 3
    inputs1(4) = 4
    inputs1(5) = 5
    inputs1(6) = 6
    inputs1(7) = 7
    inputs1(8) = 8
    inputs1(9) = 9
    inputs1(10) = 10

    Dim typeCodes1(10)
    typeCodes1(0) = 3    ' TypeCode.Boolean
    typeCodes1(1) = 5    ' TypeCode.SByte
    typeCodes1(2) = 6    ' TypeCode.Byte
    typeCodes1(3) = 7    ' TypeCode.Int16
    typeCodes1(4) = 8    ' TypeCode.UInt16
    typeCodes1(5) = 9    ' TypeCode.Int32
    typeCodes1(6) = 10   ' TypeCode.UInt32
    typeCodes1(7) = 11   ' TypeCode.Int64
    typeCodes1(8) = 12   ' TypeCode.UInt64
    typeCodes1(9) = 13   ' TypeCode.Single
    typeCodes1(10) = 14  ' TypeCode.Double

    Dim CallArguments1 As New UACallArguments
    CallArguments1.endpointDescriptor.UrlString = "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer"
    CallArguments1.nodeDescriptor.NodeId.expandedText = "nsu=http://test.org/UA/Data/ ;i=10755"
    CallArguments1.MethodNodeDescriptor.NodeId.expandedText = "nsu=http://test.org/UA/Data/ ;i=10756"
    ' Use SetXXXX methods instead of array-type property setters in Visual Basic 6.0
    CallArguments1.SetInputArguments inputs1
    CallArguments1.SetInputTypeCodes typeCodes1

    Dim inputs2(11)
    inputs2(0) = False
    inputs2(1) = 1
    inputs2(2) = 2
    inputs2(3) = 3
    inputs2(4) = 4
    inputs2(5) = 5
    inputs2(6) = 6
    inputs2(7) = 7
    inputs2(8) = 8
    inputs2(9) = 9
    inputs2(10) = 10
    inputs2(11) = "eleven"

    Dim typeCodes2(11)
    typeCodes2(0) = 3    ' TypeCode.Boolean
    typeCodes2(1) = 5    ' TypeCode.SByte
    typeCodes2(2) = 6    ' TypeCode.Byte
    typeCodes2(3) = 7    ' TypeCode.Int16
    typeCodes2(4) = 8    ' TypeCode.UInt16
    typeCodes2(5) = 9    ' TypeCode.Int32
    typeCodes2(6) = 10   ' TypeCode.UInt32
    typeCodes2(7) = 11   ' TypeCode.Int64
    typeCodes2(8) = 12   ' TypeCode.UInt64
    typeCodes2(9) = 13   ' TypeCode.Single
    typeCodes2(10) = 14  ' TypeCode.Double
    typeCodes2(11) = 18  ' TypeCode.String

    Dim CallArguments2 As New UACallArguments
    CallArguments2.endpointDescriptor.UrlString = "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer"
    CallArguments2.nodeDescriptor.NodeId.expandedText = "nsu=http://test.org/UA/Data/ ;i=10755"
    CallArguments2.MethodNodeDescriptor.NodeId.expandedText = "nsu=http://test.org/UA/Data/ ;i=10774"
    ' Use SetXXXX methods instead of array-type property setters in Visual Basic 6.0
    CallArguments2.SetInputArguments inputs2
    CallArguments2.SetInputTypeCodes typeCodes2

    Dim arguments(1) As Variant
    Set arguments(0) = CallArguments1
    Set arguments(1) = CallArguments2

    ' Instantiate the client object
    Dim Client As New EasyUAClient

    ' Perform the operation
    Dim results As Variant
    results = Client.CallMultipleMethods(arguments)

    ' Display results
    Dim i: For i = LBound(results) To UBound(results)
        OutputText = OutputText & vbCrLf
        OutputText = OutputText & "results(" & i & "):" & vbCrLf
        Dim Result As ValueArrayResult: Set Result = results(i)

        If Result.Exception Is Nothing Then
            Dim outputs As Variant: outputs = Result.ValueArray
            Dim j: For j = LBound(outputs) To UBound(outputs)
                On Error Resume Next
                OutputText = OutputText & Space(4) & "outputs(" & j & "): " & outputs(j) & vbCrLf
                If Err <> 0 Then OutputText = OutputText & Space(4) & "*** Error" & vbCrLf ' occurrs with types not recognized by VB6
                On Error GoTo 0
            Next
        Else
            OutputText = OutputText & "*** Error: " & Result.Exception & vbCrLf
        End If
    Next
End Sub

Rem This example shows how to call multiple methods, and pass arguments to and from them.

Option Explicit

Dim inputs1(10)
inputs1(0) = False
inputs1(1) = 1
inputs1(2) = 2
inputs1(3) = 3
inputs1(4) = 4
inputs1(5) = 5
inputs1(6) = 6
inputs1(7) = 7
inputs1(8) = 8
inputs1(9) = 9
inputs1(10) = 10

Dim typeCodes1(10)
typeCodes1(0) = 3    ' TypeCode.Boolean
typeCodes1(1) = 5    ' TypeCode.SByte
typeCodes1(2) = 6    ' TypeCode.Byte
typeCodes1(3) = 7    ' TypeCode.Int16
typeCodes1(4) = 8    ' TypeCode.UInt16
typeCodes1(5) = 9    ' TypeCode.Int32
typeCodes1(6) = 10   ' TypeCode.UInt32
typeCodes1(7) = 11   ' TypeCode.Int64
typeCodes1(8) = 12   ' TypeCode.UInt64
typeCodes1(9) = 13   ' TypeCode.Single
typeCodes1(10) = 14  ' TypeCode.Double

Dim CallArguments1: Set CallArguments1 = CreateObject("OpcLabs.EasyOpc.UA.OperationModel.UACallArguments")
CallArguments1.EndpointDescriptor.UrlString = "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer"
CallArguments1.NodeDescriptor.NodeId.ExpandedText = "nsu=http://test.org/UA/Data/ ;i=10755"
CallArguments1.MethodNodeDescriptor.NodeId.ExpandedText = "nsu=http://test.org/UA/Data/ ;i=10756"
CallArguments1.InputArguments = inputs1
CallArguments1.InputTypeCodes = typeCodes1

Dim inputs2(11)
inputs2(0) = False
inputs2(1) = 1
inputs2(2) = 2
inputs2(3) = 3
inputs2(4) = 4
inputs2(5) = 5
inputs2(6) = 6
inputs2(7) = 7
inputs2(8) = 8
inputs2(9) = 9
inputs2(10) = 10
inputs2(11) = "eleven"

Dim typeCodes2(11)
typeCodes2(0) = 3    ' TypeCode.Boolean
typeCodes2(1) = 5    ' TypeCode.SByte
typeCodes2(2) = 6    ' TypeCode.Byte
typeCodes2(3) = 7    ' TypeCode.Int16
typeCodes2(4) = 8    ' TypeCode.UInt16
typeCodes2(5) = 9    ' TypeCode.Int32
typeCodes2(6) = 10   ' TypeCode.UInt32
typeCodes2(7) = 11   ' TypeCode.Int64
typeCodes2(8) = 12   ' TypeCode.UInt64
typeCodes2(9) = 13   ' TypeCode.Single
typeCodes2(10) = 14  ' TypeCode.Double
typeCodes2(11) = 18  ' TypeCode.String

Dim CallArguments2: Set CallArguments2 = CreateObject("OpcLabs.EasyOpc.UA.OperationModel.UACallArguments")
CallArguments2.EndpointDescriptor.UrlString = "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer"
CallArguments2.NodeDescriptor.NodeId.ExpandedText = "nsu=http://test.org/UA/Data/ ;i=10755"
CallArguments2.MethodNodeDescriptor.NodeId.ExpandedText = "nsu=http://test.org/UA/Data/ ;i=10774"
CallArguments2.InputArguments = inputs2
CallArguments2.InputTypeCodes = typeCodes2

Dim arguments(1)
Set arguments(0) = CallArguments1
Set arguments(1) = CallArguments2

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

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

' Display results
Dim i: For i = LBound(results) To UBound(results)
    WScript.Echo
    WScript.Echo "results(" & i & "):"
    Dim Result: Set Result = results(i)

    If Result.Exception Is Nothing Then
        Dim outputs: outputs = Result.ValueArray
        Dim j: For j = LBound(outputs) To UBound(outputs)
            On Error Resume Next
            WScript.Echo Space(4) & "outputs(" & j & "): " & outputs(j)
            If Err <> 0 Then WScript.Echo Space(4) & "*** Error"   ' occurrs with types not recognized by VBScript
            On Error Goto 0
        Next
    Else
        WScript.Echo "*** Error: " & Result.Exception
    End If
Next

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

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