一、服務端程式碼

1、建立服務端socket

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

2、將ipv4地址轉換為ipAddress物件，有兩種方法：

第一種：IPAddress ipAddress = new IPAddress(new byte[] { 192, 168, 43, 163 });

第二種：IPAddress ipAddress = IPAddress.Parse("127.0.0.1");

3、將ip地址和埠號轉換為IPEndPoint物件

IPEndPoint ipEndPoint = new IPEndPoint(ipAddress, 8088);

4、將ipEndPoint繫結到服務端Socket上

 serverSocket.Bind(ipEndPoint);

5、進行監聽，10表示等待佇列中最多容納10個 請求

serverSocket.Listen(10);

6、進行接收，接收分為兩種：同步接收和非同步接收

第一種：同步接收（程式執行到這步阻塞）

Socket clientSocket = serverSocket.Accept();

第二種：非同步接收（程式不會阻塞）

serverSocket.BeginAccept(AcceptCallBack,serverSocket);  //這個函式將serverSocet作為物件傳遞給過去

AcceptCallBack()是一個函式，注意，這個函式必須將IAsyncResult型別的變數作為引數，否則BeginAccept會報錯

static void AcceptCallBack(IAsyncResult ar)
        {
            Socket serverSocket = ar.AsyncState as Socket;      //ar.AsyncState表示ar接收到的socket
            Socket clientSocket = serverSocket.EndAccept(ar);
            string msg = "hello,你好\n";
            byte[] data = System.Text.Encoding.UTF8.GetBytes(msg);
            clientSocket.Send(data);
            clientSocket.BeginReceive(dataBuffer, 0, 1024, SocketFlags.None, ReceiveCallBack, clientSocket);
            serverSocket.BeginAccept(AcceptCallBack, serverSocket);   //呼叫自身，繼續接受其他請求
        }

 static void ReceiveCallBack(IAsyncResult ar)
        {
            Socket clientSocket = null;
           try
            {
                clientSocket = ar.AsyncState as Socket; //通過ar.AsyncState獲取到Socket
                int count = clientSocket.EndReceive(ar); //count表示接收了多少位元組
                if(count == 0)  //客戶端關閉連線時服務端會無線迴圈收到0長度的位元組，因此當收到0長度的位元組時，關閉連線
                {
                    clientSocket.Close();
                    return;
                }
                string msg = Encoding.UTF8.GetString(dataBuffer, 0, count);
                Console.WriteLine("從客戶端接收到資料：" + msg);
                clientSocket.BeginReceive(dataBuffer, 0, 1024, SocketFlags.None, ReceiveCallBack, clientSocket); //迴圈回撥
            }
            catch(Exception e)
            {
                Console.WriteLine(e);
                if (clientSocket != null)
                    clientSocket.Close();
            }
            finally
            {
               
            }
        }