FtpWebRequest ListDirectory method stopping before reaching the end

Question

I'm using the following code to list the files in a directory on my FTP server. However, there are 2,914 files on the server but the following code stops after reading about 300 of them. sometimes it throws the following error:

The remote server returned an error: (450) File unavailable (e.g., file busy).

but most of the time it does not throw an error, it just stops like it is finished reading them all.

This is the code I am using.

Dim request As FtpWebRequest = DirectCast(WebRequest.Create(new_path), FtpWebRequest)
request.UseBinary = True
request.EnableSsl = True
request.Method = WebRequestMethods.Ftp.ListDirectoryDetails 
request.Credentials = New NetworkCredential("name", "password")
Dim response As FtpWebResponse = DirectCast(request.GetResponse(), FtpWebResponse)
Dim responseStream As Stream = response.GetResponseStream
Dim number_of_files As Integer = 0

dirlist.Clear()
Try
   Using reader As New StreamReader(responseStream)
     Do While reader.Peek <> -1
        Dim filename = reader.ReadLine
        dirlist.Add(filename)
        number_of_files += 1
     Loop
   End Using
Catch ex As Exception
  add_to_log(log_window, "Error : " + ex.ToString)
End Try
response.Close()

add_to_log(log_window, "Files Found : " + number_of_files.ToString)

I do not understand why it is stopping before reaching the end of the list.

Answer 1

This is basically a VB.NET variant of FtpWebRequest ListDirectory does not return all files.

The Peek condition is wrong. It breaks your loop whenever there's momentarily no data ready for reading.

Use this code:

Using reader As New StreamReader(responseStream)
    While True
        Dim filename As String = reader.ReadLine()
        If filename Is Nothing Then
            Exit While
        Else
            dirlist.Add(filename)
            number_of_files++
        End If
    End While
End Using