How to copy files from desktop to web server

[Selden McCabe]

I have a desktop application which communicates with a web server, using a
web service.

Mostly, the web service reads and writes data to Access databases on the web
server.

Now, I need to copy a large (1 MB to 30 MB) MDB file from the desktop to the
web server, replacing an existing file on the server.

What is the best way to do this from within a VB.Net windows program?

I've tried some solutions I found on the net which break the file up into
chunks, pass the chunks to the web service, and then it recombines the
chunks. But the final MDB file is a few bytes different than the original,
and crashes Access when I try to open it.

Can I use FTP or some other protocol without spending weeks programming a
custom solution?

Thanks for any suggestions!

---Selden

 

[Philip Hristov]

Selden,

You can use the FTP protocol to upload your file. Use the Indy library
to easily connect to a FTP server and upload your files -
http://www.indyproject.org/

Regards,

Philip Hristov

 

[Cor Ligthert]

Selden,

You can do an upload, you can as well take a little part of this sample I
once made, when you than even before it do a zip over the blob field, than
it can even be very efficient.

This is not the code, this is much more, however in my opinion is your
problem easily to extract from this.

\\\needs a picturebox and 4 buttons on a windowform
Private ds As New DataSet
Private abyt() As Byte
Private fo As New OpenFileDialog
Private sf As New SaveFileDialog
Private Sub Button1_Click(ByVal sender As System.Object, _
ByVal e As System.EventArgs) Handles Button1.Click
'Reading a picture from disk and put it in a bytearray
If fo.ShowDialog = DialogResult.OK Then
Dim fs As New IO.FileStream(fo.FileName, _
IO.FileMode.Open)
Dim br As New IO.BinaryReader(fs)
abyt = br.ReadBytes(CInt(fs.Length))
br.Close()
'just to show the sample without a fileread error
Dim ms As New IO.MemoryStream(abyt)
Me.PictureBox1.Image = Image.FromStream(ms)
End If
End Sub
Private Sub Button2_Click(ByVal sender As System.Object, ByVal _
e As System.EventArgs) Handles Button2.Click
'writing a picture from a bytearray to disk
If sf.ShowDialog = DialogResult.OK Then
Dim fs As New IO.FileStream(sf.FileName, _
IO.FileMode.CreateNew)
Dim bw As New IO.BinaryWriter(fs)
bw.Write(abyt)
bw.Close()
End If
End Sub
Private Sub Button3_Click(ByVal sender As System.Object, ByVal _
e As System.EventArgs) Handles Button3.Click
'writing a bytearray to a webservice dataset
Dim ws As New localhost.DataBaseUpdate
ws.SetDataset(abyt)
End Sub
Private Sub Button4_Click(ByVal sender As System.Object, _
ByVal e As System.EventArgs) Handles Button4.Click
'reading a picture from a webservice dataset
Dim ws As New localhost.DataBaseUpdate
abyt = ws.GetByte
Dim ms As New IO.MemoryStream(abyt)
Me.PictureBox1.Image = Image.FromStream(ms)
End Sub
End Class
////
\\\\Webservice
<WebMethod()> _
Public Function GetByte() As Byte()
Dim ds As New DataSet
ds.ReadXml("C:\wsblob.xml")
Return CType(ds.Tables(0).Rows(0)(0), Byte())
End Function
<WebMethod()> _
Public Sub SetDataset(ByVal abyte As Byte())
Dim ds As New DataSet
ds.Tables.Add(New DataTable("Photo"))
ds.Tables(0).Columns.Add(New DataColumn("Sample"))
ds.Tables(0).Columns(0).DataType = GetType(System.Byte())
ds.Tables(0).Rows.Add(ds.Tables(0).NewRow)
ds.Tables(0).Rows(0)(0) = abyte
ds.WriteXml("C:\wsblob.xml", XmlWriteMode.WriteSchema)
End Sub
////

I hope this helps a little bit?

Cor