How to create a folder in virtual directory by using c sharp?

 private DirectoryEntry _iisServer;
        public IISAdmin(string serverName)
        {
            _serverName = serverName;
        }
        public IISAdmin()
        {
            _serverName = "localhost";
        }
        ~IISAdmin()
        {
            _iisServer.Dispose();
            _iisServer = null;
        }
public void Connect(string username,string password)
        {
            try
            {
                if (string.IsNullOrEmpty(username))
                    _iisServer = new DirectoryEntry("IIS://" + _serverName + "/w3svc");
                else
                    _iisServer = new DirectoryEntry("IIS://" + _serverName + "/w3svc", username, password);
            }
            catch (Exception e)
            {
                throw new Exception("Could not connect to: " + _serverName, e);
            }
        }
  public List<keyvaluepair><string,>> GetAvailableWebSites()
        {
            List<keyvaluepair><string,>> retVal = new List<keyvaluepair><string,>>();
            foreach (DirectoryEntry o in _iisServer.Children)
            {
                if (o.SchemaClassName == WebServerSchemaName)
                {
                    if (o.Properties["ServerComment"] != null && o.Properties["ServerComment"].Count > 0)
                        retVal.Add(new KeyValuePair<string,>(o.Name, (string)o.Properties["ServerComment"][0]));
                    else
                        retVal.Add(new KeyValuePair<string,>(o.Name, "[website]"));
                }
            }
            return retVal;
        }
  public void CreateVirtualDirectory(int WebHostId, string nameDirectory, string realPath)
        {
            DirectoryEntry WebsiteEntity = null;
            DirectoryEntry folderRoot = null;
            foreach (DirectoryEntry o in _iisServer.Children)
                if (o.Name == WebHostId.ToString())
                {
                    WebsiteEntity = o;
                    folderRoot = o.Children.Find("Root", VirDirSchemaName);
                    break;
                }
            if (folderRoot == null) throw new Exception("Website couldnot found!");
            try
            {
                DirectoryEntry newVirDir = folderRoot.Children.Add(nameDirectory, VirDirSchemaName);
                // Create a Application
                newVirDir.Invoke("AppCreate", true);
                newVirDir.Properties["AppFriendlyName"].Insert(0, nameDirectory);
                // Set Properties
                newVirDir.Properties["AccessRead"].Insert(0, true);
                newVirDir.Properties["Path"].Insert(0, realPath);
                // Save Changes
                newVirDir.CommitChanges();
                folderRoot.CommitChanges();
                WebsiteEntity.CommitChanges();
                _iisServer.CommitChanges();
            }
            catch (Exception e)
            {
                throw new Exception("Virtual Directory " + nameDirectory + " Already Exists", e);
            }
        }
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