QuickOPC User's Guide and Reference
Examples - OPC Data Access - Browse for properties
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.NET

// This example shows how to enumerate all properties of an OPC item. For each property, it displays its Id and description.

using System;
using OpcLabs.EasyOpc.DataAccess;
using OpcLabs.EasyOpc.DataAccess.AddressSpace;
using OpcLabs.EasyOpc.OperationModel;

namespace DocExamples.DataAccess._EasyDAClient
{
    class BrowseProperties
    {
        public static void Main1()
        {
            // Instantiate the client object.
            var client = new EasyDAClient();
            DAPropertyElementCollection propertyElements;
            try
            {
                propertyElements = client.BrowseProperties("OPCLabs.KitServer.2", "Simulation.Random");
            }
            catch (OpcException opcException)
            {
                Console.WriteLine("*** Failure: {0}", opcException.GetBaseException().Message);
                return;
            }

            foreach (DAPropertyElement propertyElement in propertyElements)
                Console.WriteLine($"PropertyElements(\"{propertyElement.PropertyId.NumericalValue}\").Description: {propertyElement.Description}");
        }


        // Example output:
        //
        //PropertyElements("15008").Description: Visible
        //PropertyElements("5").Description: Item Access Rights
        //PropertyElements("2").Description: Item Value
        //PropertyElements("7").Description: Item EU Type
        //PropertyElements("15001").Description: Item Name
        //PropertyElements("4").Description: Item Timestamp
        //PropertyElements("1").Description: Item Canonical Data Type
        //PropertyElements("103").Description: Low EU
        //PropertyElements("15009").Description: Addable
        //PropertyElements("6").Description: Server Scan Rate
        //PropertyElements("15000").Description: Item ID
        //PropertyElements("3").Description: Item Quality
    }
}

COM

// This example shows how to enumerate all properties of an OPC item. For each property, it displays its Id and description.

class procedure BrowseProperties.Main;
var
  Client: OpcLabs_EasyOpcClassic_TLB._EasyDAClient;
  Count: Cardinal;
  Element: OleVariant;
  ServerDescriptor: _ServerDescriptor;
  NodeDescriptor: _DANodeDescriptor;
  PropertyElement: _DAPropertyElement;
  PropertyElementEnumerator: IEnumVariant;
  PropertyElements: _DAPropertyElementCollection;
begin
  ServerDescriptor := CoServerDescriptor.Create;
  ServerDescriptor.ServerClass := 'OPCLabs.KitServer.2';

  NodeDescriptor := CoDANodeDescriptor.Create;
  NodeDescriptor.ItemId := 'Simulation.Random';

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

  try
    PropertyElements := Client.BrowseProperties(
      ServerDescriptor,
      NodeDescriptor);
  except
    on E: EOleException do
    begin
      WriteLn(Format('*** Failure: %s', [E.GetBaseException.Message]));
      Exit;
    end;
  end;

  PropertyElementEnumerator := PropertyElements.GetEnumerator;
  while (PropertyElementEnumerator.Next(1, Element, Count) = S_OK) do
  begin
    PropertyElement := IUnknown(Element) as _DAPropertyElement;
    WriteLn('PropertyElements("', PropertyElement.PropertyId.NumericalValue, '").Description: ', PropertyElement.Description);
  end;
end;

 

See Also

Conceptual

Examples - OPC Unified Architecture