OPC Studio User's Guide and Reference
BrowseProperties(IEasyUAClient,UAEndpointDescriptor,UANodeDescriptor) Method
Example 



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OpcLabs.EasyOpcUA Assembly > OpcLabs.EasyOpc.UA Namespace > IEasyUAClientExtension Class > BrowseProperties Method : BrowseProperties(IEasyUAClient,UAEndpointDescriptor,UANodeDescriptor) Method
The client object that will perform the operation.
Endpoint descriptor. Identifies the OPC-UA server.
Node descriptor. Identifies the node in OPC server's address space.
Browses the Properties in OPC server's address space. Starts from the specified node (or Objects folder), and returns information about child nodes found. Browses the Properties, specifying an endpoint descriptor, and a starting Node Id.
Syntax
'Declaration
 
<ExtensionAttribute()>
<ElementsNotNullAttribute()>
<NotNullAttribute()>
Public Overloads Shared Function BrowseProperties( _
   ByVal client As IEasyUAClient, _
   ByVal endpointDescriptor As UAEndpointDescriptor, _
   ByVal nodeDescriptor As UANodeDescriptor _
) As UANodeElementCollection
 
'Usage
 
Dim client As IEasyUAClient
Dim endpointDescriptor As UAEndpointDescriptor
Dim nodeDescriptor As UANodeDescriptor
Dim value As UANodeElementCollection
 
value = IEasyUAClientExtension.BrowseProperties(client, endpointDescriptor, nodeDescriptor)

Parameters

client
The client object that will perform the operation.
endpointDescriptor
Endpoint descriptor. Identifies the OPC-UA server.
nodeDescriptor
Node descriptor. Identifies the node in OPC server's address space.

Return Value

The method returns a node element collection, which contains OpcLabs.EasyOpc.UA.AddressSpace.UANodeElement values. Each element contains information about a particular node found.
Exceptions
ExceptionDescription

A null reference (Nothing in Visual Basic) is passed to a method that does not accept it as a valid argument.

This is a usage error, i.e. it will never occur (the exception will not be thrown) in a correctly written program. Your code should not catch this exception.

The OPC UA operation has failed. This operation exception in uniformly used to allow common handling of various kinds of errors. The System.Exception.InnerException always contains information about the actual error cause.

This is an operation error that depends on factors external to your program, and thus cannot be always avoided. Your code must handle it appropriately.

Example

.NET

COM

// This example shows how to obtain properties under the "Server" node in the address space.
//
// Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .

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 BrowseProperties
    {
        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 properties under "Server" node.
            UANodeElementCollection nodeElementCollection;
            try
            {
                nodeElementCollection = client.BrowseProperties(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: ServerArray
        //nodeElement.NodeId: Server_ServerArray
        //nodeElement.NodeId.ExpandedText: nsu=http://opcfoundation.org/UA/ ;i=2254
        //
        //nodeElement.DisplayName: NamespaceArray
        //nodeElement.NodeId: Server_NamespaceArray
        //nodeElement.NodeId.ExpandedText: nsu=http://opcfoundation.org/UA/ ;i=2255
        //
        //nodeElement.DisplayName: ServiceLevel
        //nodeElement.NodeId: Server_ServiceLevel
        //nodeElement.NodeId.ExpandedText: nsu=http://opcfoundation.org/UA/ ;i=2267
        //
        //nodeElement.DisplayName: Auditing
        //nodeElement.NodeId: Server_Auditing
        //nodeElement.NodeId.ExpandedText: nsu=http://opcfoundation.org/UA/ ;i=2994
    }
}
// This example shows how to obtain properties under the "Server" node
// in the address space.
//
// Find all latest examples here : https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .

class procedure BrowseProperties.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 properties under "Server" node
  ServerNodeId := CoUANodeId.Create;
  ServerNodeId.StandardName := 'Server';
  try
    NodeElements := Client.BrowseProperties(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_ServerArray
  //nodeElement.NodeId.ExpandedText: nsu=http://opcfoundation.org/UA/ ;i=2254
  //nodeElement.DisplayName: ServerArray
  //
  //nodeElement.NodeId: Server_NamespaceArray
  //nodeElement.NodeId.ExpandedText: nsu=http://opcfoundation.org/UA/ ;i=2255
  //nodeElement.DisplayName: NamespaceArray
  //
  //nodeElement.NodeId: Server_ServiceLevel
  //nodeElement.NodeId.ExpandedText: nsu=http://opcfoundation.org/UA/ ;i=2267
  //nodeElement.DisplayName: ServiceLevel
  //
  //nodeElement.NodeId: Server_Auditing
  //nodeElement.NodeId.ExpandedText: nsu=http://opcfoundation.org/UA/ ;i=2994
  //nodeElement.DisplayName: Auditing

end;
Requirements

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

See Also