🚀 go-pugleaf

"Fabi�n" <fabianfierro@hotmail.com> wrote in message
news:40e99192$1@newsgroups.borland.com...

> I'm trying to transfer a jpeg.
> I have problems using a stream.

Can you be more specific please?  What exactly are you having a problem
with?


Gambit

I send the file in parts.  Then I join them again. But i doesn't work.  I
think I did it too simple

here is my code:

BYTE tBuffer[100];
TJPEGImage *tjp = new TJPEGImage();
TMemoryStream* tpms = new TMemoryStream();
//--------------------------------------------------------------------------
-
void __fastcall TfMain::wmImagenClick(TObject *Sender)
{
    BYTE Buffer[100];
    int pos = 0;

    OpenPictureDialog->FileName = GraphicFileMask(__classid(TJPEGImage));

    if (OpenPictureDialog->Execute())
    {
        TJPEGImage *jp = new TJPEGImage();
        TMemoryStream* pms = new TMemoryStream();

        jp->LoadFromFile(OpenPictureDialog->FileName);
        jp->SaveToStream(pms);

        while(pos < pms->Size - 100)
        {
            pms->Seek(pos, soFromBeginning);
            pms->ReadBuffer(Buffer, 100);

            ClientSocket->Socket->SendBuf(Buffer, 100);

            pos += 100;
        }

        pms->Seek(pos, soFromBeginning);
        pms->ReadBuffer(Buffer, pms->Size - pos);
        ClientSocket->Socket->SendBuf(Buffer, pms->Size - pos);
    }
}
//--------------------------------------------------------------------------
-
void __fastcall TfMain::ServerSocketClientRead(TObject *Sender,
      TCustomWinSocket *Socket)
{
    int total = Socket->ReceiveLength(), recived, newpacketsize;

    recived = tpms->Size;

    if(total - recived > 100)
        newpacketsize = 100;
    else
        newpacketsize = total - recived;

    Socket->ReceiveBuf(tBuffer, newpacketsize);

    tpms->WriteBuffer(tBuffer, newpacketsize);

    if(tpms->Size == total)
    {
        tjp->LoadFromStream(tpms);

        PaintBox->Canvas->Draw(0,0,tjp);
    }
}
//--------------------------------------------------------------------------
-


"Remy Lebeau (TeamB)" <gambit47.no.spam@no.spam.yahoo.com> escribi� en el
mensaje news:40e99afa$1@newsgroups.borland.com...
>
> "Fabi�n" <fabianfierro@hotmail.com> wrote in message
> news:40e99192$1@newsgroups.borland.com...
>
> > I'm trying to transfer a jpeg.
> > I have problems using a stream.
>
> Can you be more specific please?  What exactly are you having a problem
> with?
>
>
> Gambit
>
>

"Fabi�n" <fabianfierro@hotmail.com> wrote in message
news:40eab37b$1@newsgroups.borland.com...

> I send the file in parts.  Then I join them again. But i
> doesn't work.  I think I did it too simple

On the client side, are you using the TClientSocket in blocking or
non-blocking mode?  The client-side code you currently have will not work
as-is if you are using non-blocking mode, because you are not checking for
when SendBuffer() fails to send any data due to blocking.  When that
happens, you have to wait for the OnWrite event to trigger before you can
send more data again.  Otherwise, you are going to corrupt your data stream
because not all of the data will be sent correctly.

On the server side, you are assuming that the entire data stream will be
available in full every time the OnClientRead event is triggered.  That is
not correct.  The OnClientRead event is triggered whenever *any* data
arrives, even just 1 byte.  It is very common and likely that OnClientRead
will be triggered multiple times while you transferring a single data
stream.  It is your responsibility to buffer all of the incoming data until
the entire stream is received in full, and only then process the buffered
data as a whole.  In order to do that, though, you need to know how many
bytes to expect from the stream so that you can know when you have finally
received all of the data.  You should send the stream's Size before sending
the actual stream data.  Then the server can read the Size and know how many
additional bytes to expect.


Gambit