ClientClass.cs

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

namespace MyClientServerLib
{
    public class ClientClass
    {
        public string Key { get; set; }
        public string Value { get; set; }

        private string Host { get; set; }
        private int Port { get; set; }

        private bool IsConnected = false;

        public string ID { get; private set; }
        public TcpClient Tcp { get; private set; }

        private BinaryReader reader;
        private BinaryWriter writer;

        public ClientClass()
        {
            Random rnd = new Random();
            ID = AlphaNumRandom.GenerateUpperCaseString(5, rnd);
        }

        public ClientClass(TcpListener listener)
        {
            Tcp  = listener.AcceptTcpClient();

            Host = ((IPEndPoint)Tcp.Client.RemoteEndPoint).Address.ToString();
            Port = ((IPEndPoint)Tcp.Client.LocalEndPoint).Port;

            // first sent string is client ID
            ID = (new BinaryReader(Tcp.GetStream())).ReadString();

            IsConnected = true;

            NetworkStream stream = Tcp.GetStream();
            reader = new BinaryReader(stream);
            writer = new BinaryWriter(stream);

            Console.WriteLine("Client [{0}] is now connected.", ID);

        }

        public ClientClass(string host, int port)
        {
            Random rnd = new Random();
            ID = AlphaNumRandom.GenerateUpperCaseString(5, rnd);
            Host = host;
            Port = port;
        }

        public void Write(string str)
        {
            if (IsConnected)
            {
                writer.Write(str);
                writer.Flush();
            }
            else
            {
                throw new Exception("Client " + ID + " is not connected!");
            }
        }

        public string ReadString()
        {
            if (IsConnected)
            {
                return reader.ReadString();
            }
            else
            {
                throw new Exception("Client " + ID + " is not connected!");
            }
        }

        public void PrintID()
        {
            Console.WriteLine("Client ID = {0}", ID);
        }

        public void SendIdToServer()
        {
            if (IsConnected == true)
            {
                writer.Write(ID);
            }
            else
            {
                throw new Exception("Client " + ID + " is not connected!");
            }
        }

        public bool Connect()
        {
            if (IsConnected == false)
            {
                Console.WriteLine("Client [{0}] is now connected.", ID);

                IsConnected = true;

                Tcp = new TcpClient(Host, Port);

                NetworkStream stream = Tcp.GetStream();
                reader = new BinaryReader(stream);
                writer = new BinaryWriter(stream);

                return true;
            }

            return false;
        }

        public bool Disconnect()
        {
            if (IsConnected)
            {
                if (Tcp != null)
                {
                    Tcp.Close();
                    Tcp = null;

                    Console.WriteLine("Client [{0}] is now disconnected.", ID);

                    return true;
                }
            }

            return false;
        }

        public static void WriteToServer(ClientClass client)
        {
            try
            {
                while (client.Tcp.Connected)
                {
                    Console.Write("Client prompt (\"?\" for help) # ");
                    string str = Console.ReadLine();
                    client.Write(str);

                    switch (str)
                    {
                        case Commands.Help:
                            Console.WriteLine("add = add key value\n ls = list keys\n upd = update key value\n exit=terminate program");
                            break;

                        case Commands.AddKeyValue:
                            Console.WriteLine("Enter key : ");
                            string key = Console.ReadLine();
                            Console.WriteLine("Enter value : ");
                            string value = Console.ReadLine();
                            client.Write(key);
                            client.Write(value);
                            break;

                        case Commands.UpdateValue:
                            Console.WriteLine("Enter key : ");
                            string keyToUpd = Console.ReadLine();
                            Console.WriteLine("Enter val : ");
                            string valToUpd = Console.ReadLine();
                            client.Write(keyToUpd);
                            client.Write(valToUpd);
                            break;

                        case Commands.ClearScreen:
                            Console.Clear();
                            break;
                    }
                }
            }
            catch
            {
                client.Disconnect();
            }
        }

        #region read from server
        public static void ReadFromServer(ClientClass client)
        {
            try
            {
                while (client.Tcp.Connected)
                {
                    string str = client.ReadString();
                    Console.WriteLine(str);
                }
            }
            catch
            {
                client.Disconnect();
            }
        }
        #endregion
    }
}