How to determine tcp port used by Windows process in C#

Except for PID, take a look this:

IPGlobalProperties ipProperties = IPGlobalProperties.GetIPGlobalProperties();

IPEndPoint[] endPoints = ipProperties.GetActiveTcpListeners();
TcpConnectionInformation[] tcpConnections = 
    ipProperties.GetActiveTcpConnections();

foreach (TcpConnectionInformation info in tcpConnections)
{
    Console.WriteLine("Local: {0}:{1}\nRemote: {2}:{3}\nState: {4}\n", 
        info.LocalEndPoint.Address, info.LocalEndPoint.Port,
        info.RemoteEndPoint.Address, info.RemoteEndPoint.Port,
        info.State.ToString());
}
Console.ReadLine();

Source: Netstat in C#

A bit more research bring this: Build your own netstat.exe with c#. This uses P/Invoke to call GetExtendedTcpTable and using same structure as netstat.

See here for an equivalent of netstat in C#: http://towardsnext.wordpess.com/2009/02/09/netstat-in-c/

Update: Link is broken, but here's an equivalent: http://www.timvw.be/2007/09/09/build-your-own-netstatexe-with-c

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