TCP/UTP port opened?

[panchopp]

Hi guys, I'm starting with VB.NET 2003 (as requested per job's demand).
I have a requirement to look for a port and see if it is in use. Do you know of any commands to do that? Should I use some socket native function or what?
Thank you Very MUCH!

 

[Gill Bates]

Although not the most elegant solution, you can just catch the SoapException that gets thrown when the port is already in use:

TcpListener server;

try
{
    server = new TcpListener(IPAddress.Any, 80);
    server.Start();
}
catch (SocketException ex)
{
    Console.WriteLine(ex);
}