C#中Socket用法，多个聊天和单一聊天。
在C#中提供了两种网络服务，一种是Socket类，另一种是TcpListener（服务器）,TcpClient（客户端）;
至于这两种有什么区别那；MSDN上是这样解释的：
TcpClient 类， TcpListener 类 提供了一些简单的方法，用于在同步阻止模式下通过网络来连接、发送和接收流数据。
Socket 类为网络通信提供了一套丰富的方法和属性。 Socket 类允许您使用ProtocolType枚举中所列出的任何一种协议执行异步和同步数据传输。
先从第一个情景来说：第一个就是建立多人聊天的模式，就是多个客户端连接一个服务器，然后可以和多个客户端通信。就像QQ里的群聊。
首先我们来见一个服务器：
就包含一个文本框就行了，里边具体代码如下：
1 public partial class server : Form
2 {
3 private IPEndPoint ServerInfo;//存放服务器的IP和端口信息
4 private Socket ServerSocket;//服务端运行的SOCKET
5 private Thread ServerThread;//服务端运行的线程
6 private Socket[] ClientSocket;//为客户端建立的SOCKET连接
7 private int ClientNumb;//存放客户端数量
8 private byte[] MsgBuffer;//存放消息数据
9
10 private object obj;
11
12 public server()
13 {
14 InitializeComponent();
15 ListenClient();
16 }
17
18 /// <summary>
19 /// 开始服务，监听客户端
20 /// </summary>
21 private void ListenClient()
22 {
23 try
24 {
25 ServerSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
26 IPAddress ip = IPAddress.Parse("127.0.0.1");
27 ServerInfo = new IPEndPoint(ip, Int32.Parse("3000"));
28 ServerSocket.Bind(ServerInfo);
29 ServerSocket.Listen(10);
30
31 ClientSocket = new Socket[65535];
32 MsgBuffer = new byte[65535];
33 ClientNumb = 0;
34
35 ServerThread = new Thread(new ThreadStart(RecieveAccept));
36 ServerThread.Start();
37 }
38 catch (System.Exception ex)
39 {
40
41 }
42 }
43
44 /// <summary>
45 /// 添加阻塞，监听客户端
46 /// </summary>
47 private void RecieveAccept()
48 {
49 while (true)
50 {
51 //等待接受客户端连接，如果有就执行下边代码，没有就阻塞
52 ClientSocket[ClientNumb] = ServerSocket.Accept();
53 //接受客户端信息，没有阻塞，则会执行下边输出的代码；如果是Receive则不会执行下边输出代码
54 ClientSocket[ClientNumb].BeginReceive(MsgBuffer, 0, MsgBuffer.Length, SocketFlags.None,
55 new AsyncCallback(ReceiveCallback), ClientSocket[ClientNumb]);
56 this.Invoke((MethodInvoker)delegate
57 {
58 lock (this.textBox1)
59 this.textBox1.Text += "客户端：" + ClientNumb.ToString() + "连接成功！" + "\r\n";
60 });
61 ClientNumb++;
62 }
63 }
64
65 /// <summary>
66 /// 回发数据到客户端
67 /// </summary>
68 /// <param name="ar"></param>
69 private void ReceiveCallback(IAsyncResult ar)
70 {
71 try
72 {
73 Socket rSocket = (Socket)ar.AsyncState;
74 int rEnd = rSocket.EndReceive(ar);
75
76 for (int i = 0; i < ClientNumb; i++)
77 {
78 if (ClientSocket[i].Connected)
79 {
80 //发送数据到客户端
81 ClientSocket[i].Send(MsgBuffer, 0, rEnd, SocketFlags.None);
82 }
83
84 //同时接受客户端回发的数据，用于回发
85 rSocket.BeginReceive(MsgBuffer, 0, MsgBuffer.Length, 0, new AsyncCallback(ReceiveCallback), rSocket);
86 }
87 }
88 catch (System.Exception ex)
89 {
90
91 }
92 }
93 }
然后我们添加客户端代码，客户端要一个按钮和两个文本框
具体代码如下：
1 public partial class Client : Form
2 {
3 private IPEndPoint ServerInfo;
4 private Socket ClientSocket;
5 private object obj;
6
7 //信息接收缓存
8 private Byte[] MsgBuffer;
9 //信息发送存储
10 private Byte[] MsgSend;
11
12 public Client()
13 {
14 InitializeComponent();
15 ConnectServer();
16 this.button1.Click += new EventHandler(button1_Click);
17 }
18
19 /// <summary>
20 /// 打开客户端，即连接服务器
21 /// </summary>
22 private void ConnectServer()
23 {
24 try
25 {
26 ClientSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
27 MsgBuffer = new byte[65535];
28 MsgSend = new byte[65535];
29 IPAddress ip = IPAddress.Parse("127.0.0.1");
30 ServerInfo = new IPEndPoint(ip, Int32.Parse("3000"));
31 ClientSocket.Connect(ServerInfo);
32 //发送信息至服务器
33 ClientSocket.Send(Encoding.Unicode.GetBytes("用户： 进入系统！" + "\r\n"));
34 ClientSocket.BeginReceive(MsgBuffer, 0, MsgBuffer.Length, SocketFlags.None,
35 new AsyncCallback(ReceiveCallback), null);
36 this.textBox1.Text += "登录服务器成功" + "\r\n";
37 }
38 catch (System.Exception ex)
39 {
40
41 }
42 }
43
44 /// <summary>
45 /// 回调时调用
46 /// </summary>
47 /// <param name="ar"></param>
48 private void ReceiveCallback(IAsyncResult ar)
49 {
50 int rEnd = ClientSocket.EndReceive(ar);
51 this.Invoke((MethodInvoker)delegate
52 {
53 lock (this.textBox1)
54 {
55 this.textBox1.Text += Encoding.Unicode.GetString(MsgBuffer, 0, rEnd) + "\r\n";
56 }
57 });
58 ClientSocket.BeginReceive(MsgBuffer, 0, MsgBuffer.Length, 0, new AsyncCallback(ReceiveCallback), null);
59 }
60
61 /// <summary>
62 /// 发送信息
63 /// </summary>
64 /// <param name="sender"></param>
65 /// <param name="e"></param>
66 private void button1_Click(object sender, EventArgs e)
67 {
68 MsgSend = Encoding.Unicode.GetBytes("说：\n" + this.textBox2.Text + "\n\r");
69 if (ClientSocket.Connected)
70 {
71 ClientSocket.Send(MsgSend);
72 }
73 }
74
75 }
76 }
这样先运行服务器，在多运行几个客户端就可以了。
下边讲一下第二种案例:这种是多个客户端和服务器连接，每个客户端都可以和服务器通信，但是客户端之间没有通信，而且每个客户端和服务器通信时，不会影响其他客户端。
具体样式如图：
接着我们来看看具体的代码：
先来看看服务器的，样式和第一种一样，
具体代码：
1 public partial class Server : Form
2 {
3 private Socket socket = null;
4 private Thread thread = null;
5
6 public Server()
7 {
8 InitializeComponent();
9 StartListening();
10 }
11
12 ///
13 /// 开始监听客户端
14 ///
15 private void StartListening()
16 {
17 try
18 {
19 socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
20 IPAddress ipaddress = IPAddress.Parse("127.0.0.1");
21 IPEndPoint endPoint = new IPEndPoint(ipaddress, int.Parse("3000"));
22
23 socket.Bind(endPoint);
24 socket.Listen(20);
25
26 thread = new Thread(new ThreadStart(WatchConnection));
27 thread.IsBackground = true;
28 thread.Start();
29
30 this.listBox1.Text = "开始监听客户端传来的消息" + "\r\n";
31 }
32 catch (System.Exception ex)
33 {
34 this.listBox1.Text += "SocketException" + ex;
35 }
36 }
37
38 Socket[] socConnection = new Socket[12];
39 private static int clientNum = 0;
40
41 /// <summary>
42 /// 监听客户端发来的请求
43 /// </summary>
44 private void WatchConnection()
45 {
46 while (true)
47 {
48 socConnection[clientNum] = socket.Accept();
49 this.Invoke((MethodInvoker)delegate
50 {
51 this.listBox1.Text += "客户端连接成功" + "\r\n";
52 });
53
54 Thread thread = new Thread(new ParameterizedThreadStart(ServerRecMsg));
55 thread.IsBackground = true;
56 thread.Start(socConnection[clientNum]);
57 clientNum++;
58 }
59 }
60
61 /// <summary>
62 /// 接受客户端消息并发送消息
63 /// </summary>
64 /// <param name="socketClientPara"></param>
65 private void ServerRecMsg(object socketClientPara)
66 {
67 Socket socketServer = socketClientPara as Socket;
68 try
69 {
70 while (true)
71 {
72 byte[] arrServerRecMsg = new byte[1024 * 1024];
73 int length = socketServer.Receive(arrServerRecMsg);
74
75 string strSRecMsg = Encoding.UTF8.GetString(arrServerRecMsg, 0, length);
76 this.Invoke((MethodInvoker)delegate
77 {
78 this.listBox1.Text += "接收到：" + strSRecMsg + "\r\n";
79 });
80
81 byte[] arrSendMsg = Encoding.UTF8.GetBytes("收到服务器发来的消息");
82 //发送消息到客户端
83 socketServer.Send(arrSendMsg);
84 }
85 }
86 catch (System.Exception ex)
87 {
88
89 }
90 }
91 }
再来看看客户端代码：
样式和第一种也一样：
1 public partial class Client : Form
2 {
3 private Socket socketClient = null;
4 private Thread threadClient = null;
5
6 public Client()
7 {
8 InitializeComponent();
9 ConnectionServer();
10 this.button1.Click += new EventHandler(button1_Click);
11 }
12
13 /// <summary>
14 /// 连接服务器
15 /// </summary>
16 private void ConnectionServer()
17 {
18 socketClient = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
19 IPAddress ipaddress = IPAddress.Parse("127.0.0.1");
20 IPEndPoint endPoint = new IPEndPoint(ipaddress, int.Parse("3000"));
21 try
22 {
23 socketClient.Connect(endPoint);
24 threadClient = new Thread(RecMsg);
25 threadClient.IsBackground = true;
26 threadClient.Start();
27 }
28 catch (System.Exception ex)
29 {
30
31 }
32
33 }
34
35 /// <summary>
36 /// 接收服务器消息
37 /// </summary>
38 private void RecMsg()
39 {
40 while (true)
41 {
42 //内存缓冲区1M,用于临时存储接收到服务器端的消息
43 byte[] arrRecMsg = new byte[1024 * 1024];
44 //将接收到的数据放入内存缓冲区，获取其长度
45 int length = socketClient.Receive(arrRecMsg);
46 //将套接字获取到的字节数组转换为我们可以理解的字符串
47 string strRecMsg = Encoding.UTF8.GetString(arrRecMsg, 0, length);
48 this.Invoke((MethodInvoker)delegate
49 {
50 lock (this.listBox1)
51 {
52 this.listBox1.Text += "服务器：" + strRecMsg + "\r\n";
53 }
54 });
55 }
56 }
57
58 /// <summary>
59 /// 向服务器发送消息
60 /// </summary>
61 /// <param name="sender"></param>
62 /// <param name="e"></param>
63 private void button1_Click(object sender, EventArgs e)
64 {
65 ClientSendMsg(this.textBox1.Text.Trim());
66 }
67
68 /// <summary>
69 /// 发送信息到服务器
70 /// </summary>
71 /// <param name="sendMsg"></param>
72 private void ClientSendMsg(string sendMsg)
73 {
74 //将输入的字符串转化为机器可以识别的字节数组
75 byte[] arrClientSendMsg = Encoding.UTF8.GetBytes(sendMsg);
76 //发送数据
77 socketClient.Send(arrClientSendMsg);
78 this.listBox1.Text += "客户端：" + sendMsg + "\r\n";
79 }
80 }
到此两种方式就说完了，不知道说的对不对，请各位吐槽！！！，转载注明出处。
