Download/Retr File

[n0ix]

Hi, i try to use your FTP Library, but i don't get it managed to Download a File. Maybe you can provide me a simple Example or you may have a tip whats wrong with my Code?

Here is my Code

Dim _settings As New Settings
Dim _download_path As String

        'IO Stream Variablen
        Const Length As Integer = 256
        Dim buffer As [Byte]()
        Dim bytesRead As Integer = 0
        Dim bytestotalread As Integer = 0
        Dim _starttime As DateTime = DateTime.Now

        Dim _percent_downloaded As Integer = 0
        Dim _current As Long = 0
        Dim _ctime As TimeSpan
        Dim elapsed As TimeSpan
        Dim bytesPerSec As Integer = 0

        _settings = Application.Current.Resources("Settings")

        Try

            _download_path = IO.Path.Combine(_settings.DownloadDirectory, _item.FileName) 'ToDo: Einstellungen beachten (Subfolder etc)

            'ToDO: Check Download Path is exceeding 255 Chars

            'ToDO: Check FRee Disk Space

            Using _ftp_read_stream As ArxOne.Ftp.IO.FtpStream = ArxOne.Ftp.FtpClientUtility.Retr(_ftp_client, New ArxOne.Ftp.FtpPath(_item.FullPath), ArxOne.Ftp.FtpTransferMode.Binary)

                'ToDO: Set Filemode to append or create

                buffer = New Byte(8192) {}
                bytesRead = _ftp_read_stream.Read(buffer, 0, buffer.Length)

                Using _local_write_stream As New IO.FileStream(_download_path, IO.FileMode.Create, IO.FileAccess.Write, IO.FileShare.None, 8192, False)

                    While bytesRead > 0  'ToDo: CHeck if Download is stopped

                        Dim _tmp_percent_downloaded As Double = 0
                        Dim _new_perc As Integer = 0
                        Dim _download_speed As String = String.Empty

                        '  If _ftp_read_stream.Length > 0 Then

                        _local_write_stream.Write(buffer, 0, bytesRead)

                            bytesRead = _ftp_read_stream.Read(buffer, 0, Length)
                            bytestotalread += bytesRead

                            elapsed = DateTime.Now.Subtract(_starttime)

                            _tmp_percent_downloaded = CDbl(_local_write_stream.Position) / CDbl(_ftp_read_stream.Length)
                            _new_perc = CInt(_tmp_percent_downloaded * 100)

                            bytesPerSec = CInt(If(elapsed.TotalSeconds < 1, bytestotalread, bytestotalread / elapsed.TotalSeconds))

                        '  End If

                        If _new_perc <> _percent_downloaded Then 'Nicht jedesmal Updaten

                            Dim _tmp_speed As Double

                            _percent_downloaded = _new_perc

                            _current = _ftp_read_stream.Position
                            _ctime = DateTime.Now.Subtract(_starttime)

                            _tmp_speed = Math.Round(bytesPerSec / 1024, 2)

                            If _tmp_speed >= 1024 Then
                                _download_speed = Math.Round(_tmp_speed / 1024, 2) & " MB/s"
                            Else
                                _download_speed = _tmp_speed & " KB/s"
                            End If

                            '_ftp_thread_info.FileItem.SizeDownloaded = _local_write_stream.Position

                            _item.DownloadSpeed = _download_speed
                            _item.DownloadProgress = _percent_downloaded

                            ' UpdateItemProgress(_ftp_thread_info.FileItem, _ftp_thread_info.SFDLSession.SFDLSessionName, _download_speed, _percent_downloaded)

                        End If

                        'ThrottleByteTransfer(_max_bytes_per_second, bytestotalread, _ctime, bytesPerSec)

                    End While

                End Using

            End Using

        Catch ex As Exception

        End Try

Thanks in andvance.

[picrap]

Hi,

I think you are probably using it right, but it's hard to tell, since the creation of FtpClient is missing from your source code and the Retr() is drowned in a lot of other lines (written in VB... Dude, it's been 21st century for a while now, VB should be forgotten). Also you don't describe the problem, except "it doesn't work".

So a working sample here, assuming:

• ftpUri is pointing to a server, for example ftpUri = new Uri("ftp://myhost")
• ftpCredential is a valid credential such as ftpCredential = new NetworkCredential("account", "password")
• ftpFilePath points to a valid file, such as ftpFilePath = "/myfile"

using (var ftpClient = new FtpClient(ftpUri, ftpCredential)
{
    using (var r = ftpClient.Retr(ftpFilePath))
    {
        // now you have a valid stream that you can read
    }
}

This probably won't help you much, so if not, be more specific.

[n0ix]

Hi picrap,

i just tested it again with a new Test Solution and another FTP Server just to be sure.

This is the Full error i get (FTP Stream IO Error):

InnerException = {"Connection error. Code=426 ('Failure writing network stream.')"}

   bei ArxOne.Ftp.IO.FtpPassiveStream.Process[TResult](Func`1 func) in E:\programming\VB\Git Projekte\SFDL.NET\SFDL.FTP\ArxOne.Ftp\IO\FtpPassiveStream.cs:Zeile 174.
   bei ArxOne.Ftp.IO.FtpPassiveStream.Process(Action action) in E:\programming\VB\Git Projekte\SFDL.NET\SFDL.FTP\ArxOne.Ftp\IO\FtpPassiveStream.cs:Zeile 149.
   bei ArxOne.Ftp.IO.FtpPassiveStream.Release(Boolean expectEndReply) in E:\programming\VB\Git Projekte\SFDL.NET\SFDL.FTP\ArxOne.Ftp\IO\FtpPassiveStream.cs:Zeile 125.
   bei ArxOne.Ftp.IO.FtpPassiveStream.Dispose(Boolean disposing) in E:\programming\VB\Git Projekte\SFDL.NET\SFDL.FTP\ArxOne.Ftp\IO\FtpPassiveStream.cs:Zeile 96.
   bei System.IO.Stream.Close()
   bei System.IO.Stream.Dispose()
   bei DownloadTest.Module1.Main() in E:\programming\VB\Git Projekte\SFDL.NET\SFDL.NET 3\DownloadTest\Module1.vb:Zeile 103.

I also attachted my Test Solution. If you don't like VB.Net - just convert it into C#

DownloadTest.zip

An please i don't want a discussion if C# or VB.NET better - thanks.

//EDIT:

I think the Problem is that .Length and .Position in the _ftpstream Object is not available. But i need this Value to calc the Download Progress / Download Speed. When i try to Access these Values the error i posted above is thrown. So the Main Question is: Why are these Values not Present? The should be, because its a simple IO.Stream ?

[picrap]

That's right! The Position and Length properties are not available, since the Stream has its CanSeek property to false, so this is absolutely normal. Working around the problem is simple:

• You can count the bytes read (this is returned by Stream.Read()
• You can get the file size from a previous List or Mlsd

So this is normal you get an exception, however the exception itself is not.

• For you: you have enough to solve your problem
• For me: I keep the issue open in order to implement a test and fix this unwanted side effect

[n0ix]

Hi again,

thanks for the Workaround and looking into this issuse!

[picrap]

Exceptions are now NotSupportedException when the operation is not permitted, as stated in Stream documentation. I think we can close the issue, can't we?