public static bool DisplayFileFromServer(Uri serverUri,string pwd)
         {
            // The serverUri parameter should start with the ftp:// scheme.
            if (serverUri.Scheme != Uri.UriSchemeFtp)
            {
                return false;
            }
          
            WebClient request = new WebClient();
           
           //连接
            request.Credentials = new NetworkCredential("forumDB", pwd);
            try
            {
                byte[] newFileData = request.DownloadData(serverUri.ToString());
                string fileString = System.Text.Encoding.UTF8.GetString(newFileData);
                Console.WriteLine(fileString);
            }
            catch (WebException e)
            {
                Console.WriteLine(e.ToString());
            }
            return true;
        }
 static void Main(string[] args)
        {
           // Download(@"c:/","a.txt");
            DisplayFileFromServer(new Uri("ftp://117.79.93.200//13_2_db120617.rar"),"ddddd");
}