Why this code is repeating files in listbox?

Question

I want to list all files from my ftp folder, I am using this code. But it gives me twice the name of files. What is wrong with it?

private void ListFilesOnServer()
        {
            try
            {
                FtpWebRequest request = (FtpWebRequest)WebRequest.Create(ConfigurationSettings.AppSettings.Get("IncomingFtpPath"));
                request.Credentials = new NetworkCredential("user", "password");
                request.Method = WebRequestMethods.Ftp.ListDirectory;
                FtpWebResponse response = (FtpWebResponse)request.GetResponse();
                Stream responseStream = response.GetResponseStream();
                StreamReader reader = new StreamReader(responseStream);

                while (!reader.EndOfStream)
                {
                    var line = reader.ReadLine();
                    if (System.IO.Path.GetExtension(line) == ".xml")
                    {
                        WaitingListBox.Items.Add(System.IO.Path.GetFileNameWithoutExtension(line));
                    }
                }

                reader.Close();
                response.Close();
            }
            catch (Exception e)
            {
                MessageBox.Show(e.Message);
            }
        }

score 0 · Answer 1 · answered Apr 20 '14 at 20:04

Use a debugger to see what is contain in "response"
Make sure that your function is called only once.
Also, are your sure that the "duplicates" are not files with the same name but different absolute paths ?

Few remarks on your code:

Prefer using directives when manipulating streams, instead of manually closing them : here your code might throw exceptions without releasing the resources.

Avoid swallowing exceptions (even if you display them)

private void ListFilesOnServer()

{
        try
        {
     FtpWebRequest request = (FtpWebRequest)WebRequest.Create(ConfigurationSettings.AppSettings.Get("IncomingFtpPath"));

            request.Credentials = new NetworkCredential("user", "password");

            request.Method = WebRequestMethods.Ftp.ListDirectory;
            FtpWebResponse response = (FtpWebResponse)request.GetResponse();

            using(StreamReader reader = new StreamReader(response.GetResponseStream())
            {
               string line = null;
               while((line = reader.ReadLine()) != null)
               {
                if (System.IO.Path.GetExtension(line) == ".xml")
                {
                  WaitingListBox.Items.Add(System.IO.Path.GetFileNameWithoutExtension(line));
                }
               }
            }
        }
        catch (Exception e)
        {
            MessageBox.Show(e.Message);
            // throw e
        }

Why this code is repeating files in listbox?

1 Answers1