QuickOPC User's Guide and Reference
Examples - OPC UA Application - Find all our registrations in GDS
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.NET

// Shows how to find all application's registrations in the GDS.
// In order to be able to find the registration, run the example for the RegisterToGds method first.

using System;
using System.Collections.Generic;
using OpcLabs.EasyOpc.UA;
using OpcLabs.EasyOpc.UA.AddressSpace;
using OpcLabs.EasyOpc.UA.Application;
using OpcLabs.EasyOpc.UA.Application.Extensions;
using OpcLabs.EasyOpc.UA.Discovery;
using OpcLabs.EasyOpc.UA.Extensions;
using OpcLabs.EasyOpc.UA.OperationModel;

namespace UADocExamples.Application._IEasyUAClientServerApplication
{
    class FindGdsRegistrations
    {
        public static void Main1()
        {
            // Define which GDS we will work with.
            UAEndpointDescriptor gdsEndpointDescriptor =
                ((UAEndpointDescriptor)"opc.tcp://opcua.demo-this.com:58810/GlobalDiscoveryServer")
                .WithUserNameIdentity("appadmin", "demo");

            // Obtain the application interface.
            EasyUAApplication application = EasyUAApplication.Instance;

            // Display which application we are about to work with.
            Console.WriteLine("Application URI string: {0}",
                application.GetApplicationElement().ApplicationUriString);

            // Find all application's registrations in the GDS.
            IReadOnlyDictionary<UANodeId, UAApplicationElement> applicationElementDictionary;
            try
            {
                applicationElementDictionary = application.FindGdsRegistrations(gdsEndpointDescriptor);
            }
            catch (UAException uaException)
            {
                Console.WriteLine("*** Failure: {0}", uaException.GetBaseException().Message);
                return;
            }

            // Display results
            foreach (KeyValuePair<UANodeId, UAApplicationElement> pair in applicationElementDictionary)
            {
                Console.WriteLine();
                Console.WriteLine("Application ID: {0}", pair.Key);

                UAApplicationElement applicationElement = pair.Value;
                Console.WriteLine("Application element: {0}", applicationElement);
                Console.WriteLine("  Application URI string: {0}", applicationElement.ApplicationUriString);
                Console.WriteLine("  Discovery URI strings: {0}", applicationElement.DiscoveryUriStrings);
                Console.WriteLine("  Product URI string: {0}", applicationElement.ProductUriString);
            }
        }
    }
}

COM

// Shows how to find all application's registrations in the GDS.

class procedure FindGdsRegistrations.Main;
var
  Application: TEasyUAApplication;
  ApplicationElement: _UAApplicationElement;
  ApplicationElementDictionary: _UANodeIdUAApplicationElementReadOnlyDictionary;
  ApplicationId: _UANodeId;
  Count: Cardinal;
  Element: OleVariant;
  Enumerator: IEnumVARIANT;
  GdsEndpointDescriptor: _UAEndpointDescriptor;
begin
  // Define which GDS we will work with.
  GdsEndpointDescriptor := CoUAEndpointDescriptor.Create;
  GdsEndpointDescriptor.UrlString := 'opc.tcp://opcua.demo-this.com:58810/GlobalDiscoveryServer';
  GdsEndpointDescriptor.UserIdentity.UserNameTokenInfo.UserName := 'appadmin';
  GdsEndpointDescriptor.UserIdentity.UserNameTokenInfo.Password := 'demo';

  // Obtain the application interface.
  Application := TEasyUAApplication.Create(nil);

  // Display which application we are about to work with.
  WriteLn('Application URI string: ', Application.GetApplicationElement.ApplicationUriString);

  // Find all application's registrations in the GDS.
  try
    ApplicationElementDictionary := Application.FindGdsRegistrations(GdsEndpointDescriptor);
  except
    on E: EOleException do
    begin
      WriteLn(Format('*** Failure: %s', [E.GetBaseException.Message]));
    end;
  end;

  // Display results
  Enumerator := ApplicationElementDictionary.GetEnumerator;
  while (Enumerator.Next(1, Element, Count) = S_OK) do
  begin
    WriteLn;
    ApplicationId := IUnknown(Element.Key) as _UANodeId;
    WriteLn('Application ID: ', ApplicationId.ToString);

    ApplicationElement := IUnknown(Element.Value) as _UAApplicationElement;
    WriteLn('  Application URI string: ', ApplicationElement.ApplicationUriString);
    WriteLn('  Discovery URI string: ', ApplicationElement.DiscoveryUriString);
    WriteLn('  Product URI string: ', ApplicationElement.ProductUriString);
  end;
end;
See Also

Examples - OPC UA GDS and CM

Conceptual