namespace SocketServer
{
  class Program
  {
    private static byte[] result = new byte[1024];
   
    static Socket serverSocket;
    private static string client;
    private static Socket clientSocket;
    //我這里存了兩個(gè)Client，因?yàn)樽约弘娔X開(kāi)了兩個(gè)Client，不會(huì)有多的
    //理論上應(yīng)該開(kāi)一個(gè)Socket[]來(lái)保存信息，最好用一個(gè)二元組將client的信息和連接綁定起來(lái)
    //這樣就可以實(shí)現(xiàn)斷開(kāi)連接后下次登陸還是可以識(shí)別是這個(gè)Client
    private static Socket clientSocketA=null;
    private static Socket clientSocketB=null;
    
    static void Main(string[] args)
    {
      Program.SetPort(8885);
    }
    private static void SetPort(int port)
    {
      IPAddress ip = IPAddress.Parse("127.0.0.1");//set ip
      serverSocket = new Socket(AddressFamily.InterNetwork,
        SocketType.Stream, ProtocolType.Tcp);//initialize
      serverSocket.Bind(new IPEndPoint(ip, port));//bind
      serverSocket.Listen(10);
      //進(jìn)入監(jiān)聽(tīng)狀態(tài)
      Console.WriteLine("監(jiān)聽(tīng){0}成功", serverSocket.LocalEndPoint.ToString());
      //開(kāi)啟一個(gè)線程來(lái)監(jiān)聽(tīng)客戶端連接
      Thread myThread = new Thread(ListenClientConnect);
      myThread.Start();
      Console.ReadLine();

    }
    /// <summary>
    /// 監(jiān)聽(tīng)客戶端連接
    /// </summary>
    private static void ListenClientConnect()
    {
      while (true)
      {
        //Client連接上后 得到這個(gè)連接
        clientSocket = serverSocket.Accept();

        //這里我因?yàn)橹挥袃蓚€(gè)Client，所以就簡(jiǎn)單寫(xiě)了
        if (clientSocketA == null)
        {
          clientSocketA = clientSocket;
        }
        else if (clientSocketB == null)
        {
          clientSocketB = clientSocket;
        }
        else
        {
          //當(dāng)其中一個(gè)斷開(kāi)了，又重新連接時(shí)，需要再次保存連接
          if (clientSocketB.IsBound)
          {
            clientSocketA = clientSocketB;
            clientSocketB = clientSocket;
          }
          else
          {
            clientSocketB = clientSocketA;
            clientSocketA = clientSocket;
          }
          
        }
        clientSocket.Send(Encoding.ASCII.GetBytes("say hello"));
        //開(kāi)個(gè)線程接收Client信息
        Thread receivedThread = new Thread(ReceiveMessage);
        receivedThread.Start(clientSocket);

      }
    }
   
    private static void ReceiveMessage(object clientSocket)
    {
      Socket myClientSocket = (Socket) clientSocket;
      
      while (true)
      {
        try
        {
          int revceiveNumber = myClientSocket.Receive(result);
          //Console.WriteLine("接受客戶端{(lán)0}消息{1}", myClientSocket.RemoteEndPoint.ToString()
          //  , Encoding.ASCII.GetString(result, 0, revceiveNumber));
          Console.WriteLine(Encoding.ASCII.GetString(result, 0, revceiveNumber));
          if (myClientSocket == clientSocketA)
          {
            Console.WriteLine("receive from A");
            if (clientSocketB!=null&&clientSocketB.IsBound)
            {
              Console.WriteLine("a IS BOUND");
              clientSocketB.Send(result, 0, revceiveNumber, SocketFlags.None);
            }
            else
            {
              myClientSocket.Send(Encoding.ASCII.GetBytes("the people is not online! Send Failed!"));
              Console.WriteLine("對(duì)方不在線上，發(fā)送失??！");
            }
          }
          else
          {
            Console.WriteLine("receive from B");
            if (clientSocketA != null && clientSocketA.IsBound)
            {
              Console.WriteLine("a IS BOUND");
              clientSocketA.Send(result, 0, revceiveNumber, SocketFlags.None);
            }  
            else
            {
              myClientSocket.Send(Encoding.ASCII.GetBytes("the people is not online! Send Failed!"));
              Console.WriteLine("對(duì)方不在線上，發(fā)送失??！");
            }

          }
          
        }
        catch(Exception ex)
        {
          Console.WriteLine(ex.Message);
          myClientSocket.Shutdown(SocketShutdown.Both);
          myClientSocket.Close();
          break;

        }
      }

    }
  }
}

namespace SocketClient
{
  class Program
  {
    private static byte[] result = new byte[1024];
    private static Socket clientSocket;
    private static void ListenServer()
    {
      while (true)
      {
        result = new byte[1024];
        int receiveLength = clientSocket.Receive(result);
        
        Console.WriteLine("{0}", Encoding.ASCII.GetString(result, 0, receiveLength));
      }
      
    }
    static void Main(string[] args)
    {

      IPAddress ip = IPAddress.Parse("127.0.0.1");
      clientSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
      try
      {
        clientSocket.Connect(ip, 8885);
        Console.WriteLine("連接成功！");

      }
      catch (Exception e)
      {
        Console.WriteLine("連接失??！");
        return;
      }
      Thread threadRead = new Thread(ListenServer);
      threadRead.Start();
     

      while(true)
      {
        try
        {
          Thread.Sleep(1000);
          string sendMessage = Console.ReadLine();
          clientSocket.Send(Encoding.ASCII.GetBytes("Sylvia:"+sendMessage));
          
        }
        catch (Exception ex)
        {
          clientSocket.Shutdown(SocketShutdown.Both);
          clientSocket.Close();
          break;
        }

      }
      Console.WriteLine("發(fā)送完畢 按回車(chē)退出");
      Console.ReadKey();
    }
  }
}