using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

//导入的命名空间

using System.Net.Sockets;

namespace SocketClient

{

    class Program

    {

        /// <summary>

        /// Socket Server 演示

        /// </summary>

        /// <param name="args"></param>

        static void Main(string[] args)

        {

            //创建一个Socket

            var socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);

            //连接到指定服务器的指定端口

            //方法参考：http://msdn.microsoft.com/zh-cn/library/system.net.sockets.socket.connect.aspx

            socket.Connect("localhost", );

            Console.WriteLine("connect to the server");

            //实现接受消息的方法

            //方法参考：http://msdn.microsoft.com/zh-cn/library/system.net.sockets.socket.beginreceive.aspx

            socket.BeginReceive(buffer, , buffer.Length, SocketFlags.None, new AsyncCallback(ReceiveMessage), socket);

            //接受用户输入，将消息发送给服务器端

            while(true)

            {

                var message = "Message from client : " + Console.ReadLine();

                var outputBuffer = Encoding.Unicode.GetBytes(message);

                socket.BeginSend(outputBuffer, , outputBuffer.Length, SocketFlags.None, null, null);

            }

        }

        static byte[] buffer = new byte[];

        public static void ReceiveMessage(IAsyncResult ar)

        {

            try

            {

                var socket = ar.AsyncState as Socket;

                //方法参考：http://msdn.microsoft.com/zh-cn/library/system.net.sockets.socket.endreceive.aspx

                var length = socket.EndReceive(ar);

                //读取出来消息内容

                var message = Encoding.Unicode.GetString(buffer, , length);

                //显示消息

                Console.WriteLine(message);

                //接收下一个消息(因为这是一个递归的调用，所以这样就可以一直接收消息了）

                socket.BeginReceive(buffer, , buffer.Length, SocketFlags.None, new AsyncCallback(ReceiveMessage), socket);

            }

            catch(Exception ex)

            {

                Console.WriteLine(ex.Message);

            }

        }

    }

}

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

//额外导入的两个命名空间

using System.Net.Sockets;

using System.Net;

namespace SocketServer

{

    class Program

    {

        /// <summary>

        /// Socket Server 演示

        /// </summary>

        /// <param name="args"></param>

        static void Main(string[] args)

        {

            //创建一个新的Socket,这里我们使用最常用的基于TCP的Stream Socket（流式套接字）

            var socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);

            //将该socket绑定到主机上面的某个端口

            //方法参考：http://msdn.microsoft.com/zh-cn/library/system.net.sockets.socket.bind.aspx

            socket.Bind(new IPEndPoint(IPAddress.Any, ));

            //启动监听，并且设置一个最大的队列长度

            //方法参考：http://msdn.microsoft.com/zh-cn/library/system.net.sockets.socket.listen(v=VS.100).aspx

            socket.Listen();

            //开始接受客户端连接请求

            //方法参考：http://msdn.microsoft.com/zh-cn/library/system.net.sockets.socket.beginaccept.aspx

            socket.BeginAccept(new AsyncCallback(ClientAccepted), socket);

            Console.WriteLine("Server is ready!");

            Console.Read();

        }

        public static void ClientAccepted(IAsyncResult ar)

        {

            var socket = ar.AsyncState as Socket;

            //这就是客户端的Socket实例，我们后续可以将其保存起来

            var client = socket.EndAccept(ar);

            //给客户端发送一个欢迎消息

            client.Send(Encoding.Unicode.GetBytes("Hi there, I accept you request at " + DateTime.Now.ToString()));

            //实现每隔两秒钟给服务器发一个消息

            //这里我们使用了一个定时器

            var timer = new System.Timers.Timer();

            timer.Interval = 2000D;

            timer.Enabled = true;

            timer.Elapsed += (o, a) =>

            {

                //检测客户端Socket的状态

                if(client.Connected)

                {

                    try

                    {

                        client.Send(Encoding.Unicode.GetBytes("Message from server at " + DateTime.Now.ToString()));

                    }

                    catch(SocketException ex)

                    {

                        Console.WriteLine(ex.Message);

                    }

                }

                else

                {

                    timer.Stop();

                    timer.Enabled = false;

                    Console.WriteLine("Client is disconnected, the timer is stop.");

                }

            };

            timer.Start();

            //接收客户端的消息(这个和在客户端实现的方式是一样的）

            client.BeginReceive(buffer, , buffer.Length, SocketFlags.None, new AsyncCallback(ReceiveMessage), client);

            //准备接受下一个客户端请求

            socket.BeginAccept(new AsyncCallback(ClientAccepted), socket);

        }

        static byte[] buffer = new byte[];

        public static void ReceiveMessage(IAsyncResult ar)

        {

            try

            {

                var socket = ar.AsyncState as Socket;

                //方法参考：http://msdn.microsoft.com/zh-cn/library/system.net.sockets.socket.endreceive.aspx

                var length = socket.EndReceive(ar);

                //读取出来消息内容

                var message = Encoding.Unicode.GetString(buffer, , length);

                //显示消息

                Console.WriteLine(message);

                //接收下一个消息(因为这是一个递归的调用，所以这样就可以一直接收消息了）

                socket.BeginReceive(buffer, , buffer.Length, SocketFlags.None, new AsyncCallback(ReceiveMessage), socket);

            }

            catch(Exception ex){

                Console.WriteLine(ex.Message);

            }

        }

    }

}