FileStream is adding extra characters

[Hugh Janus]

Hi group,

I am using a TCPStream together with a FileStream to send a file across
a network. Everything works fine except for one thing. Always, at the
end of the file there are several lines of white space. This is no
problem for text files but for binaries it is making them corrupt. I
only realised this when using checksums to verify that the copied file
is the same.
However, I cannot seem to work out where this additional data is coming
from.

Any ideas? See below my code. At a guess I am assuming that the when
EOF is reached additional info is written to the file causing the
checksum to be different.



Dim NWStream As NetworkStream = FTPClient.GetStream

Try

Dim BytesToSend(FTPClient.SendBufferSize) As Byte
Dim FileStream As New FileStream(strFile.FullName,
FileMode.Open, FileAccess.Read)
Dim FileReader As New BinaryReader(FileStream)
Dim NumBytesRead As Integer
Dim Limit As Integer
Dim Bytes As Integer
ProgressBar.Minimum = 0
ProgressBar.Maximum = 100

Do Until Limit = strFile.Length

NumBytesRead = FileStream.Read(BytesToSend, 0,
BytesToSend.Length)
NWStream.Write(BytesToSend, 0, NumBytesRead)
Limit += NumBytesRead
Bytes += NumBytesRead
ProgressBar.Value = (Bytes / strFile.Length * 100)
ProgressBar.Update()
ProgressPercent.Text = ProgressBar.Value & "%"
ProgressPercent.Update()
NWStream.Flush()

Loop

FileStream.Close()
FileReader.Close()
NWStream.Close()
FTPClient.Close()
Threading.Thread.Sleep(1000)
ProgressBar.Value = 0
ProgressPercent.Text = ProgressBar.Value & "%"

Catch ex As Exception

MessageBox.Show(ex.Message, Me.Text, MessageBoxButtons.OK)

End Try


Thanks!

 

[Hugh Janus]

OK, this is a buffer issue it seems but I still cannot solve it.
Please help someone! I think it is a buffer issue because of the
following:

Dim numBytesRead As Integer
Dim BUFFER_SIZE As Integer = FTPClient.ReceiveBufferSize <--- this
value comes out at 8192

numBytesRead = NWstream.Read(bytesToRead, 0, BUFFER_SIZE)
FileSTR.Write(bytesToRead, 0, BUFFER_SIZE)

The file size is 211 bytes that I am testing with. So, the above code
writes out the 211 bytes and then files the file until it contains 8192
bytes. If I debug the code, after the 211 bytes have passed each
subsequent byte has a value of 0 (zero).

First of all, any ideas why it is doing this and not stopping when the
filestream has read it's 211 bytes like it is supposed to? And second,
any ideas on how to fix it? I tried setting the buffer size manually
to 211 bytes but then the file length is 8 bytes in size.

This is driving me crazy!

TIA

 

[Rocky]

FileSTR.Write(bytesToRead, 0, numBytesRead)

 

[Hugh Janus]

FileSTR.Write(bytesToRead, 0, numBytesRead)

Sigh. If only everything in life was so simple. Looking at it now, I
cannot believe how obvious my error was! I only wasted 3 days of my
life on this. :-(

Thanks.