Re: HowTo, Download first 1024 bytes of file ONLY?

Tech-Archive recommends: Repair Windows Errors & Optimize Windows Performance

NutsAboutVB wrote:
Basically, the title explains it.

I want to be able to read the first n bytes (say, 1024 bytes) of any
file (text or binary) off the internet in my vb.net application. I
specifically do not want to download the whole file (which in most
cases will be significantly large compared to the portion i do want).

Well, I'm no specialist (I started programming C# err... yesterday.

But, how about something like this horrible non-compilable code snippet
(most of which was stolen from a Microsoft C# socket example) :

int port = PORT_NUMBER;
string server = SERVER_NAME;

Socket s = null;
IPHostEntry hostEntry = null;
hostEntry = Dns.GetHostEntry(server);

foreach (IPAddress address in hostEntry.AddressList)
{
IPEndPoint ipe = new IPEndPoint(address, port);
Socket tempSocket = new Socket(ipe.AddressFamily,
SocketType.Stream, ProtocolType.Tcp);

try
{

tempSocket.Connect(ipe);

}
catch { }
finally
{
}

if (tempSocket.Connected)
{
s = tempSocket;
break;
}
else
{
// explain to the user why we can't service the request,
// and either try again or abend.

DialogResult dr = MessageBox.Show(

"We don't appear to be able to connect
to the server. Is it running ?", "Socket Error",
MessageBoxButtons.RetryCancel,
MessageBoxIcon.Exclamation,
MessageBoxDefaultButton.Button1);


continue;
}

}

// Send request to the server.

s.Send(Request, Request.Length, 0);

int bytes = 0;
i = 0;
// The following will block until the data is transmitted.
for (; ; )
{

// This returns a stream of bytes
NumberOfBytes = s.Receive(buffer, buffer.Length, 0);
string blah = Encoding.ASCII.GetString(buffer, 0,

NumberOfBytes);

// Add logic so you know when to stop
//
}

s.Close();

Ok, I've had my moment of publicly whining (this is what happens
after 3-full days of performing errant google searches).

IFYP. I've got this spiffy MSDN Universal thing, and I'd be dead in the
water without Google.

jd
.

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