Examples - OPC Unified Architecture - Browsing for data variables

.NET

// This example shows how to obtain data variables under the "Server" node in the address space.

using System;
using OpcLabs.EasyOpc.UA;
using OpcLabs.EasyOpc.UA.AddressSpace;
using OpcLabs.EasyOpc.UA.AddressSpace.Standard;
using OpcLabs.EasyOpc.UA.OperationModel;

namespace UADocExamples._EasyUAClient
{
    class BrowseDataVariables
    {
        public static void Overload2()
        {
            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();

            // Obtain data variables under "Server" node.
            UANodeElementCollection nodeElementCollection;
            try
            {
                nodeElementCollection = client.BrowseDataVariables(endpointDescriptor, UAObjectIds.Server);
            }
            catch (UAException uaException)
            {
                Console.WriteLine($"*** Failure: {uaException.GetBaseException().Message}");
                return;
            }

            // Display results
            foreach (UANodeElement nodeElement in nodeElementCollection)
            {
                Console.WriteLine();
                Console.WriteLine($"nodeElement.DisplayName: {nodeElement.DisplayName}");
                Console.WriteLine($"nodeElement.NodeId: {nodeElement.NodeId}");
                Console.WriteLine($"nodeElement.NodeId.ExpandedText: {nodeElement.NodeId.ExpandedText}");
            }
        }

        // Example output:
        //
        //nodeElement.DisplayName: ServerStatus            
        //nodeElement.NodeId: Server_ServerStatus
        //nodeElement.NodeId.ExpandedText: nsu=http://opcfoundation.org/UA/ ;i=2256
    }
}

# This example shows how to obtain data variables under the "Server" node in the address space.

#requires -Version 5.1
using namespace OpcLabs.EasyOpc.UA
using namespace OpcLabs.EasyOpc.UA.AddressSpace.Standard
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/"

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

# Obtain data variables under "Server" node.
try {
    $nodeElementCollection = [IEasyUAClientExtension]::BrowseDataVariables($client, 
        $endpointDescriptor, [UAObjectIds]::Server)
}
catch [UAException] {
    Write-Host "*** Failure: $($PSItem.Exception.GetBaseException().Message)"
    return
}

# Display results
foreach ($nodeElement in $nodeElementCollection) {
    Write-Host
    Write-Host "nodeElement.DisplayName: $($nodeElement.DisplayName)"
    Write-Host "nodeElement.NodeId: $($nodeElement.NodeId)"
    Write-Host "nodeElement.NodeId.ExpandedText: $($nodeElement.NodeId.ExpandedText)"
}


# Example output:
#
#nodeElement.DisplayName: ServerStatus            
#nodeElement.NodeId: Server_ServerStatus
#nodeElement.NodeId.ExpandedText: nsu=http://opcfoundation.org/UA/ ;i=2256

# This example shows how to obtain data variables under the "Server" node in the address space.

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

# Import .NET namespaces.
from OpcLabs.EasyOpc.UA import *
from OpcLabs.EasyOpc.UA.AddressSpace import *
from OpcLabs.EasyOpc.UA.AddressSpace.Standard 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()

# Obtain data variables under "Server" node.
try:
    nodeElementCollection = IEasyUAClientExtension.BrowseDataVariables(client,
                                                                       endpointDescriptor,
                                                                       UANodeDescriptor(UAObjectIds.Server))
except UAException as uaException:
    print('*** Failure: ' + uaException.GetBaseException().Message)
    exit()

# Display results.
for nodeElement in nodeElementCollection:
    print()
    print('nodeElement.DisplayName: ', nodeElement.DisplayName, sep='')
    print('nodeElement.NodeId: ', nodeElement.NodeId, sep='')
    print('nodeElement.NodeId.ExpandedText: ', nodeElement.NodeId.ExpandedText, sep='')

print()
print('Finished.')

' This example shows how to obtain data variables under the "Server" node in the address space.

Imports OpcLabs.EasyOpc.UA
Imports OpcLabs.EasyOpc.UA.AddressSpace
Imports OpcLabs.EasyOpc.UA.AddressSpace.Standard
Imports OpcLabs.EasyOpc.UA.OperationModel

Namespace _EasyUAClient
    Friend Class BrowseDataVariables
        Public Shared Sub Overload2()

            ' 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()

            ' Obtain variables under "Server" node
            Dim nodeElementCollection As UANodeElementCollection
            Try
                nodeElementCollection = client.BrowseDataVariables(endpointDescriptor, UAObjectIds.Server)
            Catch uaException As UAException
                Console.WriteLine("*** Failure: {0}", uaException.GetBaseException.Message)
                Exit Sub
            End Try

            ' Display results
            For Each nodeElement As UANodeElement In nodeElementCollection
                Console.WriteLine()
                Console.WriteLine("nodeElement.NodeId: {0}", nodeElement.NodeId)
                Console.WriteLine("nodeElement.DisplayName: {0}", nodeElement.DisplayName)
            Next nodeElement

            ' Example output:
            '
            'nodeElement.NodeId: nsu=http://opcfoundation.org/UA/;i=2256
            'nodeElement.DisplayName: ServerStatus            
        End Sub
    End Class
End Namespace

COM

// This example shows how to obtain data variables under the "Server" node
// in the address space.

class procedure BrowseDataVariables.Main;
var
  Client: OpcLabs_EasyOpcUA_TLB._EasyUAClient;
  Count: Cardinal;
  Element: OleVariant;
  EndpointDescriptor: string;
  NodeElement: _UANodeElement;
  NodeElementEnumerator: IEnumVariant;
  NodeElements: _UANodeElementCollection;
  ServerNodeId: _UANodeId;
begin
  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';

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

  // Obtain variables under "Server" node
  ServerNodeId := CoUANodeId.Create;
  ServerNodeId.StandardName := 'Server';
  try
    NodeElements := Client.BrowseDataVariables(EndpointDescriptor, ServerNodeId.ExpandedText);
  except
    on E: EOleException do
    begin
      WriteLn(Format('*** Failure: %s', [E.GetBaseException.Message]));
      Exit;
    end;
  end;

  // Display results
  NodeElementEnumerator := NodeElements.GetEnumerator;
  while (NodeElementEnumerator.Next(1, Element, Count) = S_OK) do
  begin
    NodeElement := IUnknown(Element) as _UANodeElement;
    WriteLn;
    WriteLn('nodeElement.NodeId: ', NodeElement.NodeId.ToString);
    WriteLn('nodeElement.NodeId.ExpandedText: ', NodeElement.NodeId.ExpandedText);
    WriteLn('nodeElement.DisplayName: ', NodeElement.DisplayName);
  end;

  // Example output:
  //
  //nodeElement.NodeId: Server_ServerStatus
  //nodeElement.NodeId.ExpandedText: nsu=http://opcfoundation.org/UA/ ;i=2256
  //nodeElement.DisplayName: ServerStatus
end;

// This example shows how to obtain data variables under the "Server" node
// in the address space.

$EndpointDescriptor = new COM("OpcLabs.EasyOpc.UA.UAEndpointDescriptor");
$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";

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

// Obtain variables under "Server" node
$ServerNodeId = new COM("OpcLabs.EasyOpc.UA.AddressSpace.UANodeId");
$ServerNodeId->StandardName = "Server";

try
{
    $NodeElements = $Client->BrowseDataVariables($EndpointDescriptor, $ServerNodeId->ExpandedText);
}
catch (com_exception $e)
{
    printf("*** Failure: %s\n", $e->getMessage());
    exit();
}

// Display results
foreach ($NodeElements as $NodeElement)
{
    printf("\n");
    printf("nodeElement.NodeId: %s\n", $NodeElement->NodeId);
    printf("nodeElement.NodeId.ExpandedText: %s\n", $NodeElement->NodeId->ExpandedText);
    printf("nodeElement.DisplayName: %s\n", $NodeElement->DisplayName);
}

// Example output:
//
//nodeElement.NodeId: Server_ServerStatus
//nodeElement.NodeId.ExpandedText: nsu=http://opcfoundation.org/UA/ ;i=2256
//nodeElement.DisplayName: ServerStatus

Rem This example shows how to obtain data variables under the "Server" node
Rem in the address space.

Public Sub BrowseDataVariables_Main_Command_Click()
    OutputText = ""

    Dim endpointDescriptor As String
    'endpointDescriptor = "http://opcua.demo-this.com:51211/UA/SampleServer"
    'endpointDescriptor = "https://opcua.demo-this.com:51212/UA/SampleServer/"
    endpointDescriptor = "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer"

    ' Instantiate the client object
    Dim Client As New EasyUAClient

    ' Obtain variables under "Server" node
    Dim serverNodeId As New UANodeId
    serverNodeId.StandardName = "Server"
    
    On Error Resume Next
    Dim NodeElements As UANodeElementCollection
    Set NodeElements = Client.BrowseDataVariables(endpointDescriptor, serverNodeId.expandedText)
    If Err.Number <> 0 Then
        OutputText = OutputText & "*** Failure: " & Err.Source & ": " & Err.Description & vbCrLf
        Exit Sub
    End If
    On Error GoTo 0

    ' Display results
    Dim NodeElement: For Each NodeElement In NodeElements
        OutputText = OutputText & vbCrLf
        OutputText = OutputText & "nodeElement.NodeId: " & NodeElement.NodeId & vbCrLf
        OutputText = OutputText & "nodeElement.NodeId.ExpandedText: " & NodeElement.NodeId.expandedText & vbCrLf
        OutputText = OutputText & "nodeElement.DisplayName: " & NodeElement.DisplayName & vbCrLf
    Next
    
    ' Example output:
    '
    'nodeElement.NodeId: Server_ServerStatus
    'nodeElement.NodeId.ExpandedText: nsu=http://opcfoundation.org/UA/ ;i=2256
    'nodeElement.DisplayName: ServerStatus
End Sub

Rem This example shows how to obtain data variables under the "Server" node in the address space.

Option Explicit

Dim endpointDescriptor: endpointDescriptor = _
    "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer"
    '"http://opcua.demo-this.com:51211/UA/SampleServer"  
    '"https://opcua.demo-this.com:51212/UA/SampleServer/"

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

' Obtain variables under "Server" node
Dim ServerNodeId: Set ServerNodeId = CreateObject("OpcLabs.EasyOpc.UA.AddressSpace.UANodeId")
ServerNodeId.StandardName = "Server"
On Error Resume Next
Dim NodeElementCollection: Set NodeElementCollection = Client.BrowseDataVariables(endpointDescriptor, ServerNodeId.ExpandedText)
If Err.Number <> 0 Then
    WScript.Echo "*** Failure: " & Err.Source & ": " & Err.Description
    WScript.Quit
End If
On Error Goto 0

' Display results
Dim NodeElement: For Each NodeElement In NodeElementCollection
    WScript.Echo 
    WScript.Echo "nodeElement.NodeId: " & NodeElement.NodeId
    WScript.Echo "nodeElement.NodeId.ExpandedText: " & NodeElement.NodeId.ExpandedText
    WScript.Echo "nodeElement.DisplayName: " & NodeElement.DisplayName
Next

' Example output:
'
'nodeElement.NodeId: Server_ServerStatus
'nodeElement.NodeId.ExpandedText: nsu=http://opcfoundation.org/UA/ ;i=2256
'nodeElement.DisplayName: ServerStatus

Conceptual

Browsing for OPC UA Nodes