tcp.exe.cs

using System;
using System.Collections.Generic;
using System.Text;
using System.Net;
using System.Net.Sockets;
using System.IO;
using System.Threading;

namespace Tcp
{
    class Program
    {
        static void Main(string[] args)
        {
            try
            {
#if DEBUG
                Console.WriteLine("attach debugger");
                Console.ReadKey(true);
#endif
                StartTcp(args);                
            }
            catch(Exception ex)
            {
                Usage();
#if DEBUG
                Console.WriteLine(ex.ToString());
#endif
            }
        }

        static string cmdInput()
        {
            Console.SetCursorPosition(0, Console.WindowHeight);
            string cmd = Console.ReadLine() + "\n";
            Console.SetCursorPosition(0, 0);
            
            return cmd;
        }

        static TcpClient tcpClient = null;
        
        static void OutputScreen()
        {
            try
            {
                byte[] buffer;

                while (tcpClient.Connected)
                {
                    // read and echo
                    int len = tcpClient.Available;
                    if (len > 0)
                    {
                        // CAN READ
                        buffer = new byte[len];

                        int read = tcpClient.GetStream().Read(buffer, 0, len);
                        string recv = Encoding.Default.GetString(buffer, 0, read);
                      
                        if (Console.CursorLeft == 2)
                        {
                            // Cheating, assume cursorLeft==2 mean we have writen ">>"
                            // Clear line and give back later

                            Console.CursorLeft = 0;
                            Console.Write("  ");
                            Console.CursorLeft = 0;

                            Console.Write(recv);
                            Console.Write(">>");
                        }
                        else
                        {
                            Console.Write(recv);
                        }                        
                    }
                }
            }
            catch(Exception ex)
            {
#if DEBUG
                Console.WriteLine(ex.ToString());
#endif
            }

            Console.WriteLine("Output session is disconnected...");
        }

        static void InputCmd()
        {
            // write
            // BUGBUG: user are not able to send special key
            // Force append '\n'
            byte[] buffer = null;
            while (tcpClient.Connected)
            {
                Console.Write(">>");
                string send = Console.ReadLine() + "\n";

                buffer = Encoding.Default.GetBytes(send);
                tcpClient.GetStream().Write(buffer, 0, buffer.Length);
            }
        }

        static void StartTcp(string[] args)
        {
            if (args.Length < 2)
            {
                Usage();
                return;
            }

            int port = -1;
            IPAddress ip = null;
            
            if (!int.TryParse(args[1], out port))
            {
                Usage();
                return;
            }

            if (IPAddress.TryParse(args[0], out ip))
            {
                tcpClient = new TcpClient();
                tcpClient.Connect(ip,port);
            }
            else
            {
                tcpClient = new TcpClient();
                tcpClient.Connect(args[0], port);
            }

            try
            {
                Console.Clear();

                Thread tOutput = new Thread(new ThreadStart(OutputScreen));
                tOutput.Start();

                Thread tInput = new Thread(new ThreadStart(InputCmd));
                tInput.Start();

                tOutput.Join();
                tInput.Join();
            }
            finally
            {
                tcpClient.Close();
            }
        }

        static void Usage()
        {
            Console.WriteLine("Usage: Tcp.exe [ip|hostname] [port]");
        }
    }
}