基于TCPIP聊天软件的代码设计

1、基于TCP/IP聊天软件的代码设计服务器端开发的详细代码：/添加的命名空间引用(原始生成的略)using System.Net;using System.Net.Sockets;using System.Threading;using System.IO;using System.Security.Cryptography;namespace EncryptedTcpServer public partial class FormServer : Form /连接的用户 System.Collections.Generic.List userList = new List(); private

2、 delegate void SetListBoxCallback(string str); private SetListBoxCallback setListBoxCallback; private delegate void SetComboBoxCallback(User user); private SetComboBoxCallback setComboBoxCallback; /使用的本机IP地址 IPAddress localAddress; /监听端口 private int port = 6788;/和书上一样 private TcpListener myListener;

3、 public FormServer() InitializeComponent(); listBoxStatus.HorizontalScrollbar = true; setListBoxCallback = new SetListBoxCallback(SetListBox); setComboBoxCallback = new SetComboBoxCallback(AddComboBoxitem); IPAddress addrIP = Dns.GetHostAddresses(Dns.GetHostName(); localAddress = addrIP0; buttonStop

4、.Enabled = false; /开始监听 private void buttonStart_Click(object sender, EventArgs e) myListener = new TcpListener(localAddress, port); myListener.Start(); SetListBox(string.Format(开始在0:1监听客户连接, localAddress, port); /创建一个线程监听客户端连接请求 ThreadStart ts = new ThreadStart(ListenClientConnect); Thread myThread

5、 = new Thread(ts); myThread.Start(); buttonStart.Enabled = false; buttonStop.Enabled = true; /接收客户端连接的线程 private void ListenClientConnect() while (true) TcpClient newClient = null; try /等待用户进入 newClient = myListener.AcceptTcpClient(); catch /当单击“停止监听”或者退出此窗体时AcceptTcpClient()会产生异常，因此可以利用此异常退出循环 brea

6、k; /每接受一个客户端连接,就创建一个对应的线程循环接收该客户端发来的信息 ParameterizedThreadStart pts = new ParameterizedThreadStart(ReceiveData); Thread threadReceive = new Thread(pts); User user = new User(newClient); threadReceive.Start(user); userList.Add(user); AddComboBoxitem(user); SetListBox(string.Format(0进入, newClient.Clie

7、nt.RemoteEndPoint); SetListBox(string.Format(当前连接用户数：0, userList.Count); /接收、处理客户端信息的线程，每客户1个线程，参数用于区分是哪个客户 private void ReceiveData(object obj) User user = (User)obj; TcpClient client = user.client; /是否正常退出接收线程 bool normalExit = false; /用于控制是否退出循环 bool exitWhile = false; while (exitWhile = false) /

8、保存接收的命令字符串 string receiveString = null; /每条命令均带有一个参数，值为true或者false，表示是否有紧跟的字节数组 string splitString = null; byte receiveBytes = null; try /从网络流中读出命令字符串 /此方法会自动判断字符串长度前缀，并根据长度前缀读出字符串 receiveString = user.br.ReadString(); splitString = receiveString.Split(,); if (splitString1 = true) /先从网络流中读出32位的长度前缀

9、int bytesLength = user.br.ReadInt32(); /然后读出指定长度的内容保存到字节数组中 receiveBytes = user.br.ReadBytes(bytesLength); catch /底层套接字不存在时会出现异常 SetListBox(接收数据失败); if (receiveString = null) if (normalExit = false) /如果停止了监听，Connected为false if (client.Connected = true) SetListBox(string.Format( 与0失去联系，已终止接收该用户信息, cl

10、ient.Client.RemoteEndPoint); break; SetListBox(string.Format(来自0：1, user.client.Client.RemoteEndPoint, receiveString); if (receiveBytes != null) SetListBox(string.Format(来自0：1, user.client.Client.RemoteEndPoint, Encoding.Default.GetString(receiveBytes); switch (splitString0)/公钥和私钥的加密解密实现 case rsaPub

11、licKey: user.rsa.FromXmlString(Encoding.Default.GetString(receiveBytes); /加密对称加密的私钥 try byte encryptedKey = user.rsa.Encrypt(user.tdes.Key, false); SendToClient(user, tdesKey,true, encryptedKey); /加密IV byte encryptedIV = user.rsa.Encrypt(user.tdes.IV, false); SendToClient(user, tdesIV,true, encrypte

12、dIV); catch (Exception err) MessageBox.Show(err.Message); break; case Logout: /格式：Logout SetListBox(string.Format(0退出, user.client.Client.RemoteEndPoint); normalExit = true; exitWhile = true; break; case Talk: /解密 string talkString = DecryptText(receiveBytes, user.tdes.Key, user.tdes.IV); if (talkSt

13、ring != null) SetListBox(string.Format(0说：1, client.Client.RemoteEndPoint, talkString); break; default: SetListBox(什么意思啊： + receiveString); break; userList.Remove(user); client.Close(); SetListBox(string.Format(当前连接用户数：0, userList.Count); / 对称加密算法加密数据的具体实现 private byte EncryptText(string str, byte K

14、ey, byte IV) /创建一个内存流 MemoryStream memoryStream = new MemoryStream(); /使用传递的私钥和IV创建加密流 CryptoStream cryptoStream = new CryptoStream(memoryStream, new TripleDESCryptoServiceProvider().CreateEncryptor(Key, IV), CryptoStreamMode.Write); /将传递的字符串转换为字节数组 byte toEncrypt = Encoding.UTF8.GetBytes(str); try

15、/将字节数组写入加密流,并清除缓冲区 cryptoStream.Write(toEncrypt, 0, toEncrypt.Length); cryptoStream.FlushFinalBlock(); /得到加密后的字节数组 byte encryptedBytes = memoryStream.ToArray(); return encryptedBytes; catch (Exception err) SetListBox(加密出错： + err.Message); return null; finally cryptoStream.Close(); memoryStream.Close

16、(); /使用对称加密算法解密接收的数据 private string DecryptText(byte dataBytes, byte Key, byte IV) /根据加密后的字节数组创建一个内存流 MemoryStream memoryStream = new MemoryStream(dataBytes); /使用传递的私钥、IV和内存流创建解密流 CryptoStream cryptoStream = new CryptoStream(memoryStream, new TripleDESCryptoServiceProvider().CreateDecryptor(Key, IV)

17、, CryptoStreamMode.Read); /创建一个字节数组保存解密后的数据 byte decryptBytes = new bytedataBytes.Length; try /从解密流中将解密后的数据读到字节数组中 cryptoStream.Read(decryptBytes, 0, decryptBytes.Length); /得到解密后的字符串 string decryptedString = Encoding.UTF8.GetString(decryptBytes); return decryptedString; catch (Exception err) SetList

18、Box(解密出错： + err.Message); return null; finally cryptoStream.Close(); memoryStream.Close(); /发送信息到客户端 private void SendToClient(User user, string command, byte bytes) /每条命令均带有一个参数，值为true或者false，表示是否有紧跟的字节数组 string splitCommand = command.Split(,); try /先将命令字符串写入网络流，此方法会自动附加字符串长度前缀 user.bw.Write(comman

19、d); SetListBox(string.Format(向0发送：1, user.client.Client.RemoteEndPoint, command); if (splitCommand1 = true) /先将字节数组的长度（32位整数）写入网络流 user.bw.Write(bytes.Length); /然后将字节数组写入网络流 user.bw.Write(bytes); user.bw.Flush(); SetListBox(string.Format(向0发送：1, user.client.Client.RemoteEndPoint, Encoding.UTF8.GetSt

20、ring(bytes); if (splitCommand0 = Talk) SetListBox(加密前内容： + textBoxSend.Text); catch SetListBox(string.Format(向0发送信息失败, user.client.Client.RemoteEndPoint); private void AddComboBoxitem(User user) if (comboBoxReceiver.InvokeRequired = true) this.Invoke(setComboBoxCallback, user); else comboBoxReceiver

21、.Items.Add(user.client.Client.RemoteEndPoint); private void SetListBox(string str) if (listBoxStatus.InvokeRequired = true) this.Invoke(setListBoxCallback, str); else listBoxStatus.Items.Add(str); listBoxStatus.SelectedIndex = listBoxStatus.Items.Count - 1; listBoxStatus.ClearSelected(); /单击停止监听按钮触发

22、的事件 private void buttonStop_Click(object sender, EventArgs e) SetListBox(string.Format(目前连接用户数：0, userList.Count); SetListBox(开始停止服务，并依次使用户退出!); for (int i = 0; i userList.Count; i+) comboBoxReceiver.Items.Remove(userListi.client.Client.RemoteEndPoint); userListi.bw.Close(); userListi.br.Close(); userListi.client.Close(); /通过停止监听让myListener.AcceptTcpClient()产生异常退出监听线程 myListener.Stop(); buttonStart.Enabled = true; buttonStop.Enabled = false; /单击发送按钮的Click事件 private void buttonSend_Click(object sende