四：SOCKET通信基本流程图：
根据socket通信基本流程图，总结通信的基本步骤：
服务器端：
第一步：创建一个用于监听连接的Socket对像；
第二步：用指定的端口号和服务器的ip建立一个EndPoint对像；
第三步：用socket对像的Bind()方法绑定EndPoint；
第四步：用socket对像的Listen()方法开始监听；
第五步：接收到客户端的连接，用socket对像的Accept()方法创建一个新的用于和客户端进行通信的socket对像;
第六步：通信结束后一定记得关闭socket;
客户端：
第一步：建立一个Socket对像；
第二步：用指定的端口号和服务器的ip建立一个EndPoint对像；
第三步：用socket对像的Connect()方法以上面建立的EndPoint对像做为参数，向服务器发出连接请求；
第四步：如果连接成功，就用socket对像的Send()方法向服务器发送信息；
第五步：用socket对像的Receive()方法接受服务器发来的信息 ;
第六步：通信结束后一定记得关闭socket；
服务端界面：
代码实现如下：
1 using System;
2 using System.Collections.Generic;
3 using System.ComponentModel;
4 using System.Data;
5 using System.Drawing;
6 using System.Linq;
7 using System.Net;
8 using System.Net.Sockets;
9 using System.Text;
10 using System.Threading.Tasks;
11 using System.Windows.Forms;
12 using System.Threading;
13 using System.IO;
14
15 namespace SocketServer
16 {
17 public partial class FrmServer : Form
18 {
19 public FrmServer()
20 {
21 InitializeComponent();
22 }
23
24 //定义回调:解决跨线程访问问题
25 private delegate void SetTextValueCallBack(string strValue);
26 //定义接收客户端发送消息的回调
27 private delegate void ReceiveMsgCallBack(string strReceive);
28 //声明回调
29 private SetTextValueCallBack setCallBack;
30 //声明
31 private ReceiveMsgCallBack receiveCallBack;
32 //定义回调：给ComboBox控件添加元素
33 private delegate void SetCmbCallBack(string strItem);
34 //声明
35 private SetCmbCallBack setCmbCallBack;
36 //定义发送文件的回调
37 private delegate void SendFileCallBack(byte[] bf);
38 //声明
39 private SendFileCallBack sendCallBack;
40
41 //用于通信的Socket
42 Socket socketSend;
43 //用于监听的SOCKET
44 Socket socketWatch;
45
46 //将远程连接的客户端的IP地址和Socket存入集合中
47 Dictionary<string, Socket> dicSocket = new Dictionary<string, Socket>();
48
49 //创建监听连接的线程
50 Thread AcceptSocketThread;
51 //接收客户端发送消息的线程
52 Thread threadReceive;
53
54 /// <summary>
55 /// 开始监听
56 /// </summary>
57 /// <param name="sender"></param>
58 /// <param name="e"></param>
59 private void btn_Start_Click(object sender, EventArgs e)
60 {
61 //当点击开始监听的时候 在服务器端创建一个负责监听IP地址和端口号的Socket
62 socketWatch = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
63 //获取ip地址
64 IPAddress ip=IPAddress.Parse(this.txt_IP.Text.Trim());
65 //创建端口号
66 IPEndPoint point=new IPEndPoint(ip,Convert.ToInt32(this.txt_Port.Text.Trim()));
67 //绑定IP地址和端口号
68 socketWatch.Bind(point);
69 this.txt_Log.AppendText("监听成功"+" \r \n");
70 //开始监听:设置最大可以同时连接多少个请求
71 socketWatch.Listen(10);
72
73 //实例化回调
74 setCallBack = new SetTextValueCallBack(SetTextValue);
75 receiveCallBack = new ReceiveMsgCallBack(ReceiveMsg);
76 setCmbCallBack = new SetCmbCallBack(AddCmbItem);
77 sendCallBack = new SendFileCallBack(SendFile);
78
79 //创建线程
80 AcceptSocketThread = new Thread(new ParameterizedThreadStart(StartListen));
81 AcceptSocketThread.IsBackground = true;
82 AcceptSocketThread.Start(socketWatch);
83 }
84
85 /// <summary>
86 /// 等待客户端的连接，并且创建与之通信用的Socket
87 /// </summary>
88 /// <param name="obj"></param>
89 private void StartListen(object obj)
90 {
91 Socket socketWatch = obj as Socket;
92 while (true)
93 {
94 //等待客户端的连接，并且创建一个用于通信的Socket
95 socketSend = socketWatch.Accept();
96 //获取远程主机的ip地址和端口号
97 string strIp=socketSend.RemoteEndPoint.ToString();
98 dicSocket.Add(strIp, socketSend);
99 this.cmb_Socket.Invoke(setCmbCallBack, strIp);
100 string strMsg = "远程主机：" + socketSend.RemoteEndPoint + "连接成功";
101 //使用回调
102 txt_Log.Invoke(setCallBack, strMsg);
103
104 //定义接收客户端消息的线程
105 Thread threadReceive = new Thread(new ParameterizedThreadStart(Receive));
106 threadReceive.IsBackground = true;
107 threadReceive.Start(socketSend);
108
109 }
110 }
111
112
113
114 /// <summary>
115 /// 服务器端不停的接收客户端发送的消息
116 /// </summary>
117 /// <param name="obj"></param>
118 private void Receive(object obj)
119 {
120 Socket socketSend = obj as Socket;
121 while (true)
122 {
123 //客户端连接成功后，服务器接收客户端发送的消息
124 byte[] buffer = new byte[2048];
125 //实际接收到的有效字节数
126 int count = socketSend.Receive(buffer);
127 if (count == 0)//count 表示客户端关闭，要退出循环
128 {
129 break;
130 }
131 else
132 {
133 string str = Encoding.Default.GetString(buffer, 0, count);
134 string strReceiveMsg = "接收：" + socketSend.RemoteEndPoint + "发送的消息:" + str;
135 txt_Log.Invoke(receiveCallBack, strReceiveMsg);
136 }
137 }
138 }
139
140 /// <summary>
141 /// 回调委托需要执行的方法
142 /// </summary>
143 /// <param name="strValue"></param>
144 private void SetTextValue(string strValue)
145 {
146 this.txt_Log.AppendText(strValue + " \r \n");
147 }
148
149
150 private void ReceiveMsg(string strMsg)
151 {
152 this.txt_Log.AppendText(strMsg + " \r \n");
153 }
154
155 private void AddCmbItem(string strItem)
156 {
157 this.cmb_Socket.Items.Add(strItem);
158 }
159
160 /// <summary>
161 /// 服务器给客户端发送消息
162 /// </summary>
163 /// <param name="sender"></param>
164 /// <param name="e"></param>
165 private void btn_Send_Click(object sender, EventArgs e)
166 {
167 try
168 {
169 string strMsg = this.txt_Msg.Text.Trim();
170 byte[] buffer = Encoding.Default.GetBytes(strMsg);
171 List<byte> list = new List<byte>();
172 list.Add(0);
173 list.AddRange(buffer);
174 //将泛型集合转换为数组
175 byte[] newBuffer = list.ToArray();
176 //获得用户选择的IP地址
177 string ip = this.cmb_Socket.SelectedItem.ToString();
178 dicSocket[ip].Send(newBuffer);
179 }
180 catch (Exception ex)
181 {
182 MessageBox.Show("给客户端发送消息出错:"+ex.Message);
183 }
184 //socketSend.Send(buffer);
185 }
186
187 /// <summary>
188 /// 选择要发送的文件
189 /// </summary>
190 /// <param name="sender"></param>
191 /// <param name="e"></param>
192 private void btn_Select_Click(object sender, EventArgs e)
193 {
194 OpenFileDialog dia = new OpenFileDialog();
195 //设置初始目录
196 dia.InitialDirectory = @"";
197 dia.Title = "请选择要发送的文件";
198 //过滤文件类型
199 dia.Filter = "所有文件|*.*";
200 dia.ShowDialog();
201 //将选择的文件的全路径赋值给文本框
202 this.txt_FilePath.Text = dia.FileName;
203 }
204
205 /// <summary>
206 /// 发送文件
207 /// </summary>
208 /// <param name="sender"></param>
209 /// <param name="e"></param>
210 private void btn_SendFile_Click(object sender, EventArgs e)
211 {
212 List<byte> list = new List<byte>();
213 //获取要发送的文件的路径
214 string strPath = this.txt_FilePath.Text.Trim();
215 using (FileStream sw = new FileStream(strPath,FileMode.Open,FileAccess.Read))
216 {
217 byte[] buffer = new byte[2048];
218 int r = sw.Read(buffer, 0, buffer.Length);
219 list.Add(1);
220 list.AddRange(buffer);
221
222 byte[] newBuffer = list.ToArray();
223 //发送
224 //dicSocket[cmb_Socket.SelectedItem.ToString()].Send(newBuffer, 0, r+1, SocketFlags.None);
225 btn_SendFile.Invoke(sendCallBack, newBuffer);
226
227
228 }
229
230 }
231
232 private void SendFile(byte[] sendBuffer)
233 {
234
235 try
236 {
237 dicSocket[cmb_Socket.SelectedItem.ToString()].Send(sendBuffer, SocketFlags.None);
238 }
239 catch (Exception ex)
240 {
241 MessageBox.Show("发送文件出错:"+ex.Message);
242 }
243 }
244
245 private void btn_Shock_Click(object sender, EventArgs e)
246 {
247 byte[] buffer = new byte[1] { 2};
248 dicSocket[cmb_Socket.SelectedItem.ToString()].Send(buffer);
249 }
250
251 /// <summary>
252 /// 停止监听
253 /// </summary>
254 /// <param name="sender"></param>
255 /// <param name="e"></param>
256 private void btn_StopListen_Click(object sender, EventArgs e)
257 {
258 socketWatch.Close();
259 socketSend.Close();
260 //终止线程
261 AcceptSocketThread.Abort();
262 threadReceive.Abort();
263 }
264 }
265 }
客户端界面
代码实现如下：
1 using System;
2 using System.Collections.Generic;
3 using System.ComponentModel;
4 using System.Data;
5 using System.Drawing;
6 using System.Linq;
7 using System.Text;
8 using System.Threading.Tasks;
9 using System.Windows.Forms;
10 using System.Net.Sockets;
11 using System.Net;
12 using System.Threading;
13 using System.IO;
14
15 namespace SocketClient
16 {
17 public partial class FrmClient : Form
18 {
19 public FrmClient()
20 {
21 InitializeComponent();
22 }
23
24 //定义回调
25 private delegate void SetTextCallBack(string strValue);
26 //声明
27 private SetTextCallBack setCallBack;
28
29 //定义接收服务端发送消息的回调
30 private delegate void ReceiveMsgCallBack(string strMsg);
31 //声明
32 private ReceiveMsgCallBack receiveCallBack;
33
34 //创建连接的Socket
35 Socket socketSend;
36 //创建接收客户端发送消息的线程
37 Thread threadReceive;
38
39 /// <summary>
40 /// 连接
41 /// </summary>
42 /// <param name="sender"></param>
43 /// <param name="e"></param>
44 private void btn_Connect_Click(object sender, EventArgs e)
45 {
46 try
47 {
48 socketSend = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
49 IPAddress ip = IPAddress.Parse(this.txt_IP.Text.Trim());
50 socketSend.Connect(ip, Convert.ToInt32(this.txt_Port.Text.Trim()));
51 //实例化回调
52 setCallBack = new SetTextCallBack(SetValue);
53 receiveCallBack = new ReceiveMsgCallBack(SetValue);
54 this.txt_Log.Invoke(setCallBack, "连接成功");
55
56 //开启一个新的线程不停的接收服务器发送消息的线程
57 threadReceive = new Thread(new ThreadStart(Receive));
58 //设置为后台线程
59 threadReceive.IsBackground = true;
60 threadReceive.Start();
61 }
62 catch (Exception ex)
63 {
64 MessageBox.Show("连接服务端出错:" + ex.ToString());
65 }
66 }
67
68 /// <summary>
69 /// 接口服务器发送的消息
70 /// </summary>
71 private void Receive()
72 {
73 try
74 {
75 while (true)
76 {
77 byte[] buffer = new byte[2048];
78 //实际接收到的字节数
79 int r = socketSend.Receive(buffer);
80 if (r == 0)
81 {
82 break;
83 }
84 else
85 {
86 //判断发送的数据的类型
87 if (buffer[0] == 0)//表示发送的是文字消息
88 {
89 string str = Encoding.Default.GetString(buffer, 1, r - 1);
90 this.txt_Log.Invoke(receiveCallBack, "接收远程服务器:" + socketSend.RemoteEndPoint + "发送的消息:" + str);
91 }
92 //表示发送的是文件
93 if (buffer[0] == 1)
94 {
95 SaveFileDialog sfd = new SaveFileDialog();
96 sfd.InitialDirectory = @"";
97 sfd.Title = "请选择要保存的文件";
98 sfd.Filter = "所有文件|*.*";
99 sfd.ShowDialog(this);
100
101 string strPath = sfd.FileName;
102 using (FileStream fsWrite = new FileStream(strPath, FileMode.OpenOrCreate, FileAccess.Write))
103 {
104 fsWrite.Write(buffer, 1, r - 1);
105 }
106
107 MessageBox.Show("保存文件成功");
108 }
109 }
110
111
112 }
113 }
114 catch (Exception ex)
115 {
116 MessageBox.Show("接收服务端发送的消息出错:" + ex.ToString());
117 }
118 }
119
120
121 private void SetValue(string strValue)
122 {
123 this.txt_Log.AppendText(strValue + "\r \n");
124 }
125
126 /// <summary>
127 /// 客户端给服务器发送消息
128 /// </summary>
129 /// <param name="sender"></param>
130 /// <param name="e"></param>
131 private void btn_Send_Click(object sender, EventArgs e)
132 {
133 try
134 {
135 string strMsg = this.txt_Msg.Text.Trim();
136 byte[] buffer = new byte[2048];
137 buffer = Encoding.Default.GetBytes(strMsg);
138 int receive = socketSend.Send(buffer);
139 }
140 catch (Exception ex)
141 {
142 MessageBox.Show("发送消息出错:" + ex.Message);
143 }
144 }
145
146 private void FrmClient_Load(object sender, EventArgs e)
147 {
148 Control.CheckForIllegalCrossThreadCalls = false;
149 }
150
151 /// <summary>
152 /// 断开连接
153 /// </summary>
154 /// <param name="sender"></param>
155 /// <param name="e"></param>
156 private void btn_CloseConnect_Click(object sender, EventArgs e)
157 {
158 //关闭socket
159 socketSend.Close();
160 //终止线程
161 threadReceive.Abort();
162 }
163 }
164 }