实验六 即时通信系统.doc

实验六 即时通信系统1实验目的（1）练习TcpClient和TcpListener的用法。（2）练习NetworkStream的用法。（3）练习StreamReadr和StreamWriter的用法。（4）练习线程的创建和使用方法。 （5）练习解决TCP协议消息边界问题的另一种方法。2建议用时建议用4-6小时完成本实验，或者根据自己的理解情况调整实际需要的时间。3实验内容开发一个简单的基于TCP的即时通信系统，服务器端和客户端设计界面分别如下图所示。功能要求：（1）任何一个客户端，均可以与服务器进行通信。（2）服务器要能显示客户端连接的状态，当客户端连接成功后，要自动及时告知客户端已经连接成功的信息。（3）客户端和服务器建立连接后，即可以和服务器聊天，也可以和其他任何客户聊天，用StreamReader和StreamWriter对象实现字符串的接收和发送。（4）不论客户端何时退出程序，服务器都要做出正确判断，并显示该客户连接和断开连接的情况。 图1-3 客户端设计界面图1-2 服务器设计界面 4实验要求（1）使用强类型的List泛型列表userList保存连接的用户。（2）定义委托解决一个线程调用另一个线程控件的问题。5实验步骤提示服务器端：（1）创建一个名为SyncChatServer的Windows应用程序，将Form1.cs换名为MainForm.cs，设计界面如图1-2所示。（2）在解决方案资源管理器中，鼠标右键单击项目名，选择【添加】【类】，添加一个类文件User.cs，用于保存与客户通信需要的信息。参考代码如下。class User public TcpClient client get; private set; public StreamReader sr get; private set; public StreamWriter sw get; private set; public User(TcpClient client) this.client = client; NetworkStream netStream = client.GetStream(); sr = new StreamReader(netStream, System.Text.Encoding.UTF8); sw = new StreamWriter(netStream, System.Text.Encoding.UTF8); public void Close() sr.Close(); sw.Close(); client.Close(); （3）在SyncChatServer中添加对应的代码和事件。代码如下。public partial class MainForm : Form / 保存连接的所有用户 private List userList = new List(); / 使用的本机IP地址 IPAddress localAddress; / 监听端口 private const int port = 51888; private TcpListener myListener; / 是否正常退出所有接收线程 bool isNormalExit = false; public MainForm() InitializeComponent(); listBoxStatus.HorizontalScrollbar = true; IPAddress addrIP = Dns.GetHostAddresses(Dns.GetHostName(); localAddress = addrIP0; buttonStop.Enabled = false; / 【开始监听】按钮的Click事件 private void buttonStart_Click(object sender, EventArgs e) myListener = new TcpListener(localAddress, port); myListener.Start(); AddItemToListBox(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 Thread myThread = new Thread(ListenClientConnect); myThread.Start(); buttonStart.Enabled = false; buttonStop.Enabled = true; / 接收客户端连接 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 break; /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 User user = new User(newClient); Thread threadReceive = new Thread(ReceiveData); threadReceive.Start(user); AddUser(user); SendIPAddressesToClients(); /显示工作状态 AddItemToListBox(string.Format(0进入, newClient.Client.RemoteEndPoint); AddItemToListBox(string.Format(当前连接用户数：0, userList.Count); / / 接收、处理客户端信息，应该给每客户都创建1个线程执行此方法 / / 客户信息 private void ReceiveData(object userState) User user = (User)userState; TcpClient client = user.client; while (isNormalExit = false) string receiveString = null; try /从网络流中读出字符串，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.sr.ReadLine(); catch if (isNormalExit = false) AddItemToListBox(string.Format(与0失去联系，已终止接收该用户信息, client.Client.RemoteEndPoint); RemoveUser(user); break; AddItemToListBox(string.Format(来自0：1, user.client.Client.RemoteEndPoint, receiveString); string splitString = receiveString.Split(,); string sendString = ; switch (splitString0) case Login: /格式：Login sendString = Hello，我是服务器，你好!; SendToClient(user, sendString); break; case Logout: /格式：Logout AddItemToListBox(string.Format(0退出, user.client.Client.RemoteEndPoint); RemoveUser(user); /将变化后的用户IP发送给所有用户 /SendIPAddressesToClients(); return; case Talk: /格式：Talk,对话内容 if (splitString1 = client.Client.LocalEndPoint.ToString() | splitString1 = Dns.GetHostName() +:+ port.ToString() AddItemToListBox(string.Format(0说：1, client.Client.RemoteEndPoint, receiveString.Substring(splitString0.Length + splitString1.Length + 2); else /向交谈双方分别发送信息 receiveString = receiveString.Insert(5, client.Client.RemoteEndPoint.ToString()+,); /发起交谈方 SendToClient(user, receiveString); /接受交谈方 for (int i = 0; i userList.Count; i+) if (userListi.client.Client.RemoteEndPoint.ToString() = splitString1) SendToClient(userListi, receiveString); break; default: AddItemToListBox(什么意思啊： + receiveString); break; / / 发送信息给客户 / / 用于区分是哪个客户 / 要发送的信息 private void SendToClient(User user, string str) try /将字符串写入网络流，此方法会自动附加字符串长度前缀 user.sw.WriteLine(str); user.sw.Flush(); AddItemToListBox(string.Format(向0发送：1, user.client.Client.RemoteEndPoint, str); catch AddItemToListBox(string.Format(向0发送信息失败, user.client.Client.RemoteEndPoint); private delegate void SendIPAddressesToClientsDelegate(); / / 把和服务器连接的所有客户端的端点信息发给每个客户端 / private void SendIPAddressesToClients() if (this.InvokeRequired = true) SendIPAddressesToClientsDelegate d = new SendIPAddressesToClientsDelegate(SendIPAddressesToClients); this.Invoke(d); else StringBuilder temp = new StringBuilder(comboBoxReceiver.Items.Count * 20); temp.Append(AllIP); int intLen = comboBoxReceiver.Items.Count; for (int i = 0; i intLen; i+) temp.AppendFormat(,0, comboBoxReceiver.Itemsi); for (int j = 0; j intLen; j+) SendToClient(userListj, temp.ToString(); private delegate void AddUserDelegate(User user); / / 添加用户 / private void AddUser(User user) if (this.InvokeRequired = true) AddUserDelegate d = new AddUserDelegate(AddUser); this.Invoke(d, user); else userList.Add(user); comboBoxReceiver.Items.Add(user.client.Client.RemoteEndPoint); private delegate void RemoveUserDelegate(User user); / / 移除用户 / private void RemoveUser(User user) if (this.InvokeRequired = true) RemoveUserDelegate d = new RemoveUserDelegate(RemoveUser); this.Invoke(d, user); else comboBoxReceiver.Items.Remove(user.client.Client.RemoteEndPoint); comboBoxReceiver.Text = string.Empty; userList.Remove(user); user.Close(); AddItemToListBox(string.Format(当前连接用户数：0, userList.Count); private delegate void AddItemToListBoxDelegate(string str); / / 在ListBox中追加状态信息 / / 要追加的信息 private void AddItemToListBox(string str) if (listBoxStatus.InvokeRequired = true) AddItemToListBoxDelegate d = new AddItemToListBoxDelegate(AddItemToListBox); this.Invoke(d, str); else listBoxStatus.Items.Add(str); listBoxStatus.SelectedIndex = listBoxStatus.Items.Count - 1; listBoxStatus.ClearSelected(); / / 【停止监听】按钮的Click事件 / private void buttonStop_Click(object sender, EventArgs e) AddItemToListBox(开始停止服务，并依次使用户退出!); isNormalExit = true; for (int i = userList.Count - 1; i = 0; i-) RemoveUser(userListi); /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; / / 【发送】按钮的Click事件 / private void buttonSend_Click(object sender, EventArgs e) int index = comboBoxReceiver.SelectedIndex; if (index = -1) MessageBox.Show(请先选择接收方，然后再单击发送); else User user = (User)userListindex; SendToClient(user, textBoxSend.Text); textBoxSend.Clear(); / / 关闭窗口时触发的事件 / private void MainForm_FormClosing(object sender, FormClosingEventArgs e) if (myListener != null) /触发buttonStop的Click事件 buttonStop.PerformClick(); / / 在控件具有焦点且用户按下并释放某键后触发的事件 / private void textBoxSend_KeyPress(object sender, KeyPressEventArgs e) if (e.KeyChar = (char)Keys.Return) /触发buttonSend的Click事件 buttonSend.PerformClick(); 客户端：（1）创建一个名为SyncChatClient的Windows应用程序，将Form1.cs换名为MainForm.cs，设计界面如图1-3所示。（2）在ChatClient中添加对应的代码和事件，参考代码如下。public partial class MainForm : Form private bool isExit = false; private TcpClient client; private StreamReader sr; private StreamWriter sw; public MainForm() InitializeComponent(); listBoxStatus.HorizontalScrollbar = true; / / 【连接服务器】按钮的Click事件 / private void buttonConnect_Click(object sender, EventArgs e) try /实际使用时要将Dns.GetHostName()改为服务器域名 client = new TcpClient(Dns.GetHostName(), 51888); AddListBoxItem(string.Format(本机EndPoint：0, client.Client.LocalEndPoint); AddListBoxItem(与服务器建立连接成功); catch AddListBoxItem(与服务器连接失败); return; buttonConnect.Enabled = false; /获取网络流 NetworkStream networkStream = client.GetStream(); /将网络流作为二进制读写对象 sr = new StreamReader(networkStream, System.Text.Encoding.UTF8); sw = new StreamWriter(networkStream, System.Text.Encoding.UTF8); SendString(Login); Thread threadReceive = new Thread(ReceiveData); threadReceive.Start(); / / 接收数据 / private void ReceiveData() string receiveString = null; while (isExit = false) try /从网络流中读出字符串 receiveString = sr.ReadLine(); catch if (isExit = false) MessageBox.Show(与服务器失去联系，请单击“确定”退出系统。); break; if (receiveString != null) string splitString = receiveString.Split(,); switch (splitString0) case AllIP: /格式：Login AddComboBoxItem(receiveString); AddListBoxItem(收到： + receiveString); break; case Talk: /格式：Talk,发送谈话方端点,对话内容 AddListBoxItem(string.Format(0对1说：2, splitString1, splitString2, receiveString.Substring(splitString0.Length + splitString1.Length + splitString2.Length + 3); break; default: AddListBoxItem(收到： + receiveString); break; Application.Exit(); private delegate void AddComboBoxDelegate(string str); / / 在ListBox中添加一项信息 / / 要添加的信息 private void AddComboBoxItem(string str) if (listBoxStatus.InvokeRequired = true) AddComboBoxDelegate d = new AddComboBoxDelegate(AddComboBoxItem); this.Invoke(d, str); else /把自己的信息去掉 str=str.Replace(string.Format(,0, client.Client.LocalEndPoint), ); string splitString = str.Split(,); /实际使用时要将Dns.GetHostName()改为服务器域名 splitString0 = string.Format(0:1, Dns.GetHostName(), 51888); comboBoxReceiver.Items.Clear(); comboBoxReceiver.Items.AddRange(splitString); / / 发送数据 / / 要发送的数据 private void SendString(string str) try /将字符串写入网络流，此方法会自动附加字符串长度前缀 sw.WriteLine(str); sw.Flush(); AddListBoxItem(string.Format(发送：0, str); catch AddListBoxItem(发送失败!); private