Check Opened Port

public static bool CheckOpenedPort(this int port)
{
    IPGlobalProperties ipGlobalProperties = IPGlobalProperties.GetIPGlobalProperties();
    IPEndPoint[] tcpConnInfoArray = ipGlobalProperties.GetActiveTcpListeners();

    foreach (IPEndPoint endpoint in tcpConnInfoArray)
    {
        if (endpoint.Port == port)
        {
            return true;
        }
    }
    return false;
}

int portNumber = 507;
 MessageBox.Show(portNumber.CheckOpenedPort().ToString());