if (item != "." && item != "..") {
   FtpWebRequest request = (FtpWebRequest) FtpWebRequest.Create(new Uri(ftpSource + item));
   request.Proxy = null;
   request.Credentials = new NetworkCredential(ftpUser, ftpPassword);
   request.Method = WebRequestMethods.Ftp.GetFileSize;

   FtpWebResponse response = (FtpWebResponse) request.GetResponse();
   long size = response.ContentLength;
   MessageBox.Show(item + " " + size.ToString());
   response.Close();
 }