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vb.net FTP Download / File Size

Posted on 2007-12-06
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Last Modified: 2013-12-16
I have aprogram which connects to the FTP server I have the upload peice working I can get he file directory yada yada where the problem lies is
1 - Cant get it to download the code completely(ill attach my download code and the error)
2 - I need to figure out how toget the file size befor I download so I can implement my progress bar and you will see where I have tried "response.contentlength" but it returns "-1"
------------
Problem for #1 is listed underneath the code
-------------------

Thanks for any help!
Private Sub btnDownload_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnDownload.Click
        fdb.SelectedPath = Application.StartupPath
        fdb.ShowDialog()
        Dim tempSaveDir = fdb.SelectedPath
        Try
            Dim outputStream As FileStream = New FileStream(fdb.SelectedPath + "\\" + lbFiles.SelectedItem, FileMode.OpenOrCreate)
            Dim clsRequest As System.Net.FtpWebRequest = DirectCast(System.Net.WebRequest.Create(tempurl & "/" & lbFiles.SelectedItem), System.Net.FtpWebRequest)
            clsRequest.Credentials = New System.Net.NetworkCredential(Form1.tbUser.Text, Form1.tbPass.Text)
            clsRequest.Method = System.Net.WebRequestMethods.Ftp.DownloadFile
 
            Dim response As FtpWebResponse = clsRequest.GetResponse
            Dim ftpStream As Stream = response.GetResponseStream()
            Dim cl As String = response.ContentLength
            MsgBox(cl)
            Dim bufferSize As Integer = 1024
            Dim readCount As Integer
            Dim buffer(bufferSize) As Byte
            Dim tempCount = 0
            ProgressBar.Value = 0
            While True
                readCount = ftpStream.Read(buffer, 0, bufferSize)
                If readCount > 0 Then
                    outputStream.Write(buffer, 0, readCount)
                    'ProgressBar.Value = (tempCount / cl) * 100
                End If
                'MsgBox(outputstre)
            End While
 
            ftpStream.Flush()
            outputStream.Flush()
            ftpStream.Dispose()
            outputStream.Dispose()
            response.Close()
 
        Catch ui As UriFormatException
            MsgBox("ui " + ui.Message)
        Catch io As IOException
            MsgBox("IO " + io.Message)
        Catch ex As Exception
            MsgBox("EX " + ex.Message)
        End Try
    End Sub
 
 
ERROR I receive when trying to download I get about 75% of the way thru the download - 
EX Cannot access adisposed object.
Object name: 'system.net.sockets.networkstream'.
 
Then it just stops and aborts the download all this doesnt make sense because im not disposing any object untill after the read AND I commented the code out and still doenst work.

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Question by:aumudin
3 Comments
 
LVL 19

Accepted Solution

by:
Rimvis earned 1200 total points
ID: 20426234
You have an endless loop. Maybe this is the reason? It never stops, even after download is finished

Take a look at this code:

...
            clsRequest.Method = System.Net.WebRequestMethods.Ftp.DownloadFile
 
            Dim cl As String
            Dim response As FtpWebResponse = clsRequest.GetResponse
 
            If response.ContentLength > 0 Then
                cl = response.ContentLength
            Else
                'Get filesize from status message
                Dim r As Regex = New Regex("(?<size>\d+[ ]bytes)")
                Dim m As Match = r.Matches(response.StatusDescription)("size")
                cl = m.Value
            End If
 
            Dim ftpStream As Stream = response.GetResponseStream()
            Dim bufferSize As Integer = 1024
            Dim readCount As Integer
            Dim buffer(bufferSize) As Byte
            Dim tempCount = 0
            ProgressBar.Value = 0
            While True
                readCount = ftpStream.Read(buffer, 0, bufferSize)                
                If readCount > 0 Then
                    outputStream.Write(buffer, 0, readCount)
                    tempCount += readCount
                    ProgressBar.Value = (tempCount / cl) * 100
                    ProgressBar.Refresh()
                Else
                    'Exit loop
                    Exit While
                End If
                'MsgBox(outputstre)
            End While
...

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LVL 16

Assisted Solution

by:gnoon
gnoon earned 800 total points
ID: 20426266
This's from MSDN

"
ContentLength returns 1 if no data was returned in the response or if the server did not send content length information. The return value is greater than or equal to zero if data was or should have been returned
"

Print the URL to the console, then copy/paste at a browser. Hits Enter and see if any file is downloaded.

Console.WriteLine(tempurl & "/" & lbFiles.SelectedItem)

Output?

P.S. I noticed that you're facing infinite loop of reading (no such line of break), and I think it's the cause of error. Try change it to this
While True
	readCount = ftpStream.Read(buffer, 0, bufferSize)
	If readCount > 0 Then
		outputStream.Write(buffer, 0, readCount)
		'ProgressBar.Value = (tempCount / cl) * 100
	Else
		Exit While
	End If
End While

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LVL 4

Author Comment

by:aumudin
ID: 20427746
Alright and as far as getting the file size I found the answer its ftpwebresponse.getFileSize pretty simple lol as far as the infinite loop I cant belive I didnt see that...... Thanks guys
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