Socket同步異步通信

1、套接字簡(jiǎn)介：套接字最早是Unix的，window是借鑒過(guò)來(lái)的。TCP/IP協(xié)議族提供三種套接字：流式、數(shù)據(jù)報(bào)式、原始套接字。其中原始套接字允許對(duì)底層協(xié)議直接訪問(wèn)，一般用于檢驗(yàn)新協(xié)議或者新設(shè)備問(wèn)題，很少使用。套接字編程原理：延續(xù)文件作用思想，打開(kāi)-讀寫(xiě)-關(guān)閉的模式。C/S編程模式如下：Ø  服務(wù)器端：打開(kāi)通信通道，告訴本地機(jī)器，愿意在該通道上接受客戶請(qǐng)求監(jiān)聽(tīng)，等待客戶請(qǐng)求接受請(qǐng)求，創(chuàng)建專用鏈接進(jìn)行讀寫(xiě)處理完畢，關(guān)閉專用鏈接關(guān)閉通信通道（當(dāng)然其中監(jiān)聽(tīng)到關(guān)閉專用鏈接可以重復(fù)循環(huán)）Ø  客戶端：打開(kāi)通信通道，連接服務(wù)器數(shù)據(jù)交互關(guān)閉信道。Soc

2、ket通信方式：Ø  同步：客戶端在發(fā)送請(qǐng)求之后必須等到服務(wù)器回應(yīng)之后才可以發(fā)送下一條請(qǐng)求。串行運(yùn)行Ø  異步：客戶端請(qǐng)求之后，不必等到服務(wù)器回應(yīng)之后就可以發(fā)送下一條請(qǐng)求。并行運(yùn)行套接字模式：Ø  阻塞：執(zhí)行此套接字調(diào)用時(shí)，所有調(diào)用函數(shù)只有在得到返回結(jié)果之后才會(huì)返回。在調(diào)用結(jié)果返回之前，當(dāng)前進(jìn)程會(huì)被掛起。即此套接字一直被阻塞在網(wǎng)絡(luò)調(diào)用上。Ø  非阻塞：執(zhí)行此套接字調(diào)用時(shí)，調(diào)用函數(shù)即使得不到得到返回結(jié)果也會(huì)返回。套接字工作步驟：Ø  服務(wù)器監(jiān)聽(tīng)：監(jiān)

3、聽(tīng)時(shí)服務(wù)器端套接字并不定位具體客戶端套接字，而是處于等待鏈接的狀態(tài)，實(shí)時(shí)監(jiān)控網(wǎng)絡(luò)狀態(tài)Ø  客戶端鏈接：客戶端發(fā)出鏈接請(qǐng)求，要連接的目標(biāo)是服務(wù)器端的套接字。為此客戶端套接字必須描述服務(wù)器端套接字的服務(wù)器地址與端口號(hào)。Ø  鏈接確認(rèn)：是指服務(wù)器端套接字監(jiān)聽(tīng)到客戶端套接字的鏈接請(qǐng)求時(shí)，它響應(yīng)客戶端鏈接請(qǐng)求，建立一個(gè)新的線程，把服務(wù)器端套接字的描述發(fā)送給客戶端，一旦客戶端確認(rèn)此描述，則鏈接建立好。而服務(wù)器端的套接字繼續(xù)處于監(jiān)聽(tīng)狀態(tài)，繼續(xù)接受其他客戶端套接字請(qǐng)求。在TCP/IP網(wǎng)絡(luò)中，IP網(wǎng)絡(luò)交互分類兩大類：面向連接的交互與面向無(wú)連接的交互。S

4、ocket構(gòu)造函數(shù)：public socket(AddressFamily 尋址類型, SocketType 套接字類型, ProtocolType 協(xié)議類型)。但需要注意的是套接字類型與協(xié)議類型并不是可以隨便組合。SocketTypeProtocolType描述StreamTcp面向連接DgramUdp面向無(wú)連接RawIcmp網(wǎng)際消息控制RawRaw基礎(chǔ)傳輸協(xié)議Socket類的公共屬性：屬性名描述AddressFamily獲取Socket的地址族Available獲取已經(jīng)從網(wǎng)絡(luò)接收且可供讀取的數(shù)據(jù)量Blocking獲取或設(shè)置一個(gè)值，只是socket是否處于阻塞模

5、式Connected獲取一個(gè)值，指示當(dāng)前連接狀態(tài)Handle獲取socket的操作系統(tǒng)句柄LocalEndPoint獲取本地終端EndPointRemoteEndPoint獲取遠(yuǎn)程終端EndPointProtocolType獲取協(xié)議類型SocketType獲取SocketType類型Socket常用方法：Bind(EndPoint)服務(wù)器端套接字需要綁定到特定的終端，客戶端也可以先綁定再請(qǐng)求連接Listen(int)監(jiān)聽(tīng)端口，其中parameters表示最大監(jiān)聽(tīng)數(shù)Accept()接受客戶端鏈接，并返回一個(gè)新的鏈接，用于處理同客戶端的通信問(wèn)題 Send()發(fā)送數(shù)據(jù)Send(byte)簡(jiǎn)

6、單發(fā)送數(shù)據(jù)Send(byte,SocketFlag)使用指定的SocketFlag發(fā)送數(shù)據(jù)Send(byte, int, SocketFlag)使用指定的SocketFlag發(fā)送指定長(zhǎng)度數(shù)據(jù)Send(byte, int, int, SocketFlag)使用指定的SocketFlag，將指定字節(jié)數(shù)的數(shù)據(jù)發(fā)送到已連接的socket(從指定偏移量開(kāi)始)Receive()接受數(shù)據(jù)Receive(byte)簡(jiǎn)單接受數(shù)據(jù)Receive (byte,SocketFlag)使用指定的SocketFlag接受數(shù)據(jù)Receive (byte, int, SocketFlag)使用指定的SocketFlag接受指

7、定長(zhǎng)度數(shù)據(jù)Receive (byte, int, int, SocketFlag)使用指定的SocketFlag，從綁定的套接字接收指定字節(jié)數(shù)的數(shù)據(jù)，并存到指定偏移量位置的緩沖區(qū) Connect(EndPoint)連接遠(yuǎn)程服務(wù)器ShutDown(SocketShutDown)禁用套接字，其中SocketShutDown為枚舉，Send禁止發(fā)送，Receive為禁止接受，Both為兩者都禁止Close()關(guān)閉套接字，釋放資源異步通信方法：BeginAccept(AsynscCallBack,object)開(kāi)始一個(gè)一步操作接受一個(gè)連接嘗試。參數(shù)：一個(gè)委托。一個(gè)對(duì)象。對(duì)象包含此請(qǐng)求的狀態(tài)信

8、息。其中回調(diào)方法中必須使用EndAccept方法。應(yīng)用程序調(diào)用BegineAccept方法后，系統(tǒng)會(huì)使用單獨(dú)的線程執(zhí)行指定的回調(diào)方法并在EndAccept上一直處于阻塞狀態(tài)，直至監(jiān)測(cè)到掛起的鏈接。EndAccept會(huì)返回新的socket對(duì)象。供你來(lái)同遠(yuǎn)程主機(jī)數(shù)據(jù)交互。不能使用返回的這個(gè)socket接受隊(duì)列中的任何附加連接。調(diào)用BeginAccept當(dāng)希望原始線程阻塞的時(shí)候，請(qǐng)調(diào)用WaitHandle.WaitOne方法。當(dāng)需要原始線程繼續(xù)執(zhí)行時(shí)請(qǐng)?jiān)诨卣{(diào)方法中使用ManualResetEvent的set方法BeginConnect(EndPoint, AsyncCallBack, Object)

9、回調(diào)方法中必須使用EndConnect()方法。Object中存儲(chǔ)了連接的詳細(xì)信息。BeginSend(byte, SocketFlag, AsyncCallBack, Object) BegineReceive(byte, SocketFlag, AsyncCallBack, Object) BegineDisconnect(bool, AsyncCallBack, Object) 給出同步通信與異步通信的示例：同步通信：預(yù)定義結(jié)構(gòu)體，同步通信沒(méi)有多線程異步委托回調(diào)，所以無(wú)需預(yù)定義結(jié)構(gòu)體客戶端Client：class Program 

10、0;      static void Main()                    try                int port =

11、 2000;                string host = ""                IPAddress ip = IPAddress.Parse(host); 

12、0;              IPEndPoint ipe = new IPEndPoint(ip, port);/把ip和端口轉(zhuǎn)化為IPEndPoint實(shí)例                Socket c = new Socket(Ad

13、dressFamily.InterNetwork, SocketType.Stream,ProtocolType.Tcp);/創(chuàng)建一個(gè)Socket                Console.WriteLine("Conneting.");              

14、  c.Connect(ipe);/連接到服務(wù)器                string sendStr = "hello!This is a socket test"                byte bs

15、= Encoding.ASCII.GetBytes(sendStr);                Console.WriteLine("Send Message");                c.Send(bs, bs.Length, 0)

16、;/發(fā)送測(cè)試信息                string recvStr = ""                byte recvBytes = new byte1024;   

17、60;            int bytes;                bytes = c.Receive(recvBytes, recvBytes.Length, 0);/從服務(wù)器端接受返回信息        

18、0;       recvStr += Encoding.ASCII.GetString(recvBytes, 0, bytes);                Console.WriteLine("Client Get Message:0", recvStr);/顯示服務(wù)器返回信息    

19、60;           c.Close();                        catch (ArgumentNullException e)      

20、          Console.WriteLine("ArgumentNullException: 0", e);                        catch (SocketException e)&#

21、160;               Console.WriteLine("SocketException: 0", e);                        Console.W

22、riteLine("Press Enter to Exit");            Console.ReadLine();        服務(wù)器端：class Program    static void Main()       &#

23、160;    try            int port = 2000;            string host = ""          

24、;  IPAddress ip = IPAddress.Parse(host);            IPEndPoint ipe = new IPEndPoint(ip, port);            Socket s = new Socket(Ad

25、dressFamily.InterNetwork, SocketType.Stream,ProtocolType.Tcp);/創(chuàng)建一個(gè)Socket類            s.Bind(ipe);/綁定2000端口            s.Listen(0);/開(kāi)始監(jiān)聽(tīng)      

26、60;     Console.WriteLine("Wait for connect");            Socket temp = s.Accept();/為新建連接創(chuàng)建新的Socket。            Console.WriteLine("Get

27、a connect");            string recvStr = ""            byte recvBytes = new byte1024;          

28、  int bytes;            bytes = temp.Receive(recvBytes, recvBytes.Length, 0);/從客戶端接受信息            recvStr += Encoding.ASCII.GetString(recvBytes, 0, bytes); 

29、;           Console.WriteLine("Server Get Message:0", recvStr);/把客戶端傳來(lái)的信息顯示出來(lái)            string sendStr = "Ok!Client Send Message Sucessful!"  &#

30、160;         byte bs = Encoding.ASCII.GetBytes(sendStr);            temp.Send(bs, bs.Length, 0);/返回客戶端成功信息            temp.Close()

31、;            s.Close();                catch (ArgumentNullException e)            Console.

32、WriteLine("ArgumentNullException: 0", e);        catch (SocketException e)            Console.WriteLine("SocketException: 0", e);       

33、; Console.WriteLine("Press Enter to Exit");        Console.ReadLine();       異步通信：客戶端Client：預(yù)定義結(jié)構(gòu)體，用于異步委托之間的傳遞。用戶根據(jù)自己需要定制即可public class StateObject    / Client socket.  &

34、#160; public Socket workSocket = null;    / Size of receive buffer.    public const int BufferSize = 256;    / Receive buffer.    public byte buffer = new byteBufferSize;

35、    / Received data string.    public StringBuilder sb = new StringBuilder();正文：public class AsynchronousClient    / The port number for the remote device.    private const int

36、0;port = 11000;    / ManualResetEvent instances signal completion.    private static ManualResetEvent connectDone = new ManualResetEvent(false);    private static ManualResetEvent sendDone = new&

37、#160;ManualResetEvent(false);    private static ManualResetEvent receiveDone = new ManualResetEvent(false);    / The response from the remote device.private static String response = String.Empty;   &#

38、160; private static void StartClient()        / Connect to a remote device.        try            / Establish the remote endpoint for the so

39、cket.            / The name of the remote device is "".            IPHostEntry ipHostInfo = Dns.Resolve("");       

40、     IPAddress ipAddress = ipHostInfo.AddressList0;            IPEndPoint remoteEP = new IPEndPoint(ipAddress, port);             

41、/ Create a TCP/IP socket.            Socket client = new Socket(AddressFamily.InterNetwork,                SocketType.Stream, ProtocolType.T

42、cp);             / Connect to the remote endpoint.            client.BeginConnect(remoteEP,              

43、  new AsyncCallback(ConnectCallback), client);            connectDone.WaitOne();             / Send test data to the remote device.    

44、        Send(client, "This is a test<EOF>");            sendDone.WaitOne();             / Receive the response fro

45、m the remote device.            Receive(client);            receiveDone.WaitOne();             / Write the response

46、 to the console.            Console.WriteLine("Response received : 0", response);             / Release the socket.        &#

47、160;   client.Shutdown(SocketShutdown.Both);            client.Close();        catch (Exception e)            Conso

48、le.WriteLine(e.ToString();         private static void ConnectCallback(IAsyncResult ar)            try            /

49、 Retrieve the socket from the state object.            Socket client = (Socket)ar.AsyncState;             / Complete the connection.      &#

50、160;     client.EndConnect(ar);             Console.WriteLine("Socket connected to 0",                client.RemoteEndPo

51、int.ToString();             / Signal that the connection has been made.            connectDone.Set();            &#

52、160;   catch (Exception e)            Console.WriteLine(e.ToString();         private static void Receive(Socket client)     

53、       try            / Create the state object.            StateObject state = new StateObject();     &#

54、160;      state.workSocket = client;             / Begin receiving the data from the remote device.            client.BeginReceive(state.buffer,

55、0, StateObject.BufferSize, 0,                new AsyncCallback(ReceiveCallback), state);                catch (Exception 

56、;e)            Console.WriteLine(e.ToString();         private static void ReceiveCallback(IAsyncResult ar)           &#

57、160;try            / Retrieve the state object and the client socket            / from the asynchronous state object.          

58、60; StateObject state = (StateObject)ar.AsyncState;            Socket client = state.workSocket;             / Read data from the remote device.  

59、0;         int bytesRead = client.EndReceive(ar);             if (bytesRead > 0)                /

60、 There might be more data, so store the data received so far.                state.sb.Append(Encoding.ASCII.GetString(state.buffer, 0, bytesRead);            &#

61、160;    / Get the rest of the data.                client.BeginReceive(state.buffer, 0, StateObject.BufferSize, 0,             

62、60;      new AsyncCallback(ReceiveCallback), state);                        else           

63、;     / All the data has arrived; put it in response.                if (state.sb.Length > 1)               

64、0;                    response = state.sb.ToString();                        

65、60;       / Signal that all bytes have been received.                receiveDone.Set();                &#

66、160;           catch (Exception e)            Console.WriteLine(e.ToString();         private static void Send(Sock

67、et client, String data)            / Convert the string data to byte data using ASCII encoding.        byte byteData = Encoding.ASCII.GetBytes(data);     &

68、#160;   / Begin sending the data to the remote device.        client.BeginSend(byteData, 0, byteData.Length, 0,            new AsyncCallback(SendCallback), client);  

69、0;      private static void SendCallback(IAsyncResult ar)            try            / Retrieve the socket from the state object.&#

70、160;           Socket client = (Socket)ar.AsyncState;             / Complete sending the data to the remote device.          

71、  int bytesSent = client.EndSend(ar);            Console.WriteLine("Sent 0 bytes to server.", bytesSent);             / Signal that all bytes have bee

72、n sent.            sendDone.Set();        catch (Exception e)            Console.WriteLine(e.ToString();    &#

73、160;    public static int Main(String args)            StartClient();        return 0;    服務(wù)器端Server：預(yù)定義結(jié)構(gòu)體，用于異步委托之間的傳遞。同客戶端的一致。不再贅述正文：/ Sta

74、te object for reading client data asynchronouslypublic class AsynchronousSocketListener    / Thread signal.    public static ManualResetEvent allDone = new ManualResetEvent(false);    public Asynchron

75、ousSocketListener()    public static void StartListening()            / Data buffer for incoming data.        byte bytes = new Byte1024;   &

76、#160;    / Establish the local endpoint for the socket.        / The DNS name of the computer        / running the listener is "".         /IPHos

77、tEntry ipHostInfo = Dns.Resolve(Dns.GetHostName();        IPHostEntry ipHostInfo = Dns.Resolve("");        IPAddress ipAddress = ipHostInfo.AddressList0;     

78、60;  IPEndPoint localEndPoint = new IPEndPoint(ipAddress, 11000);        / Create a TCP/IP socket.        Socket listener = new Socket(AddressFamily.InterNetwork,SocketType.Stream,

79、ProtocolType.Tcp);        / Bind the socket to the local endpoint and listen for incoming connections.        try            listener.Bind(localEndPoint); 

80、           listener.Listen(100);            while (true)                / Set the event to nonsignal

81、ed state.                allDone.Reset();                / Start an asynchronous socket to listen for connections.    &#

82、160;           Console.WriteLine("Waiting for a connection.");                listener.BeginAccept(new AsyncCallback(AcceptCallback),listener); &

83、#160;              / Wait until a connection is made before continuing.                allDone.WaitOne();       

84、60;                    catch (Exception e)            Console.WriteLine(e.ToString();       

85、60;Console.WriteLine("nPress ENTER to continue.");        Console.Read();        public static void AcceptCallback(IAsyncResult ar)          

86、;  / Signal the main thread to continue.        allDone.Set();        / Get the socket that handles the client request.        Socket listener = (Socket)ar.AsyncStat

87、e;        Socket handler = listener.EndAccept(ar);        / Create the state object.        StateObject state = new StateObject();     

88、   state.workSocket = handler;        handler.BeginReceive(state.buffer, 0, StateObject.BufferSize, 0,newAsyncCallback(ReadCallback), state);        public static void ReadCallback(IAsy

89、ncResult ar)            String content = String.Empty;        / Retrieve the state object and the handler socket        / from the asynchronous s

90、tate object.        StateObject state = (StateObject)ar.AsyncState;        Socket handler = state.workSocket;        / Read data from the client socket.   

91、     int bytesRead = handler.EndReceive(ar);        if (bytesRead > 0)                    / There    m

92、ight be more data, so store the data received so far.            state.sb.Append(Encoding.ASCII.GetString(state.buffer, 0, bytesRead);            / Check for end-of-file tag. If it

93、 is not there, read            / more data.            content = state.sb.ToString();            if (content.IndexO

94、f("<EOF>") > -1)                / All the data has been read from the                / client. Display it on the console.                Console.WriteLine("Read 0 bytes from socket. n Data : 1",                content.Length, content