// This example shows how to recursively browse the nodes in the OPC address space.
using System;
using System.Diagnostics;
using OpcLabs.EasyOpc;
using OpcLabs.EasyOpc.DataAccess;
 
namespace DocExamples
{
    namespace _EasyDAClient
    {
        partial class BrowseNodes
        {
            public static void Recursive()
            {
                var stopwatch = new Stopwatch();
                stopwatch.Start();
 
                var easyDAClient = new EasyDAClient();
                _branchCount = 0;
                _leafCount = 0;
                BrowseFromNode(easyDAClient, "OPCLabs.KitServer.2", "");
 
                stopwatch.Stop();
                Console.WriteLine("Browsing has taken (milliseconds): {0}", stopwatch.ElapsedMilliseconds);
                Console.WriteLine("Branch count: {0}", _branchCount);
                Console.WriteLine("Leaf count: {0}", _leafCount);
            }
 
            private static void BrowseFromNode(
                EasyDAClient client,
                ServerDescriptor serverDescriptor,
                DANodeDescriptor parentNodeDescriptor)
            {
                Debug.Assert(client != null);
                Debug.Assert(serverDescriptor != null);
                Debug.Assert(parentNodeDescriptor != null);
 
                // Obtain all node elements under parentNodeDescriptor
                var nodeFilter = new DANodeFilter();    // no filtering whatsoever
                DANodeElementCollection nodeElementCollection = 
                    client.BrowseNodes(serverDescriptor, parentNodeDescriptor, nodeFilter);
                // Remark: that BrowseNodes(...) may also throw OpcException; a production code should contain handling for 
                // it, here omitted for brevity.
 
                foreach (DANodeElement nodeElement in nodeElementCollection)
                {
                    Debug.Assert(nodeElement != null);
 
                    Console.WriteLine(nodeElement);
 
                    // If the node is a branch, browse recursively into it.
                    if (nodeElement.IsBranch)
                    {
                        _branchCount++;
                        BrowseFromNode(client, serverDescriptor, nodeElement);
                    }
                    else
                    {
                        _leafCount++;
                    }
                }
            }
 
            private static int _branchCount;
            private static int _leafCount;
        }
    }
}