A simple C# app to get the version of a remote IPs SSH client

sshv.cs

using System;
using System.Net.Sockets;
using System.Text;

namespace SSHv
{
    internal class Program
    {
        private static void Main(string[] args)
        {
            string IP = "";
            int port = 22;
            if (args.Length == 0)
            {
                Console.WriteLine("Reelix's SSH Version Detector");
                Console.WriteLine("sshv IP [port]");
                Environment.Exit(0);
            }
            else if (args.Length > 0)
            {
                IP = args[0];
                if (args.Length == 2)
                {
                    port = int.Parse(args[1]);
                }
            }
            TcpClient tcpClient = new TcpClient();
            try
            {
                tcpClient.Connect(IP, port);
            }
            catch (Exception ex)
            {
                Console.WriteLine("Cannot connect: " + ex.Message);
                tcpClient.Close();
                Environment.Exit(0);
            }
            if (tcpClient.Connected)
            {
                if (tcpClient.ReceiveBufferSize > 0)
                {
                    byte[] dataBytes = new byte[tcpClient.ReceiveBufferSize];
                    tcpClient.ReceiveTimeout = 5000;
                    try
                    {
                        tcpClient.GetStream().Read(dataBytes, 0, tcpClient.ReceiveBufferSize);
                    }
                    catch (Exception ex)
                    {
                        Console.WriteLine("Connected, but no response");
                        Environment.Exit(0);
                    }
                    string theData = Encoding.ASCII.GetString(dataBytes);
                    theData = theData.Replace("\0", "").Replace(Environment.NewLine, "");
                    if (theData.Length == 0)
                    {
                        Console.WriteLine("Connected, but no response");
                    }
                    else
                    {
                        Console.WriteLine(theData);
                    }
                }
                else
                {
                    Console.WriteLine("No response :<");
                }
            }
            else
            {
                Console.WriteLine("Cannot connect :<");
            }
        }
    }
}