客户端程序的代码编写:
布置界面。往界面上添加一个ListBox控件(用于显示用户列表),一个RichTextBox控件(用于显示聊天消息以及系统消息),一个 TextBox控件(用于发送消息),一个CheckBox控件(确定是否为悄悄话),一个StatusBar控件(name=StatusBar1)以 及四个Button控件(分别为“连接”、“断开连接”、“开始记录”、“发送”)。
当客户端试图和服务器端进行连接时,一个连接必须建立而且得向服务器端进行注册。 ConnectionServer()函数运用一个TcpClient来和服务器端取得连接,同时创建一个NetworkStream来发送消息。还有, 端口号和服务器端的是保持一致的。
先声明如下变量:
private System.Net.Sockets.TcpClient clientSocket;
private System.Net.Sockets.NetworkStream ns;
private System.IO.StreamReader sr;
ConnectionServer()函数如下:
private void ConnectionServer()
{
StatusBar1.Text = "正在连接到服务器……";
try
{
clientSocket = new System.Net.Sockets.TcpClient(serverAddress,serverPort);
ns = clientSocket.GetStream();
sr = new System.IO.StreamReader(ns);
connected = true;
}
catch (Exception)
{
MessageBox.Show("不能连接到服务器!","错误", MessageBoxButtons.OK, MessageBoxIcon.Exclamation);
StatusBar1.Text = "已断开连接";
}
}
在和服务器端连接成功后,程序就用RegisterWithServer()函数向服务器端发送一个CONN命令。该命令先是发送该用户的名称,然后从服务器端获得其他所有用户的列表,所有用户列表是在ListBox控件中显示的。
RegisterWithServer()函数如下:
private void RegisterWithServer()
{
try
{
string command = "CONN|" + ChatOut.Text;
Byte[] outBytes = System.Text.Encoding.ASCII.GetBytes(command.ToCharArray());
ns.Write(outBytes,0,outBytes.Length);
string serverResponse = sr.ReadLine();
serverResponse.Trim();
string[] tokens = serverResponse.Split(new Char[]{'|'});
if(tokens[0] == "LIST")
{
StatusBar1.Text = "已连接";
btnCloseConnection.Enabled = true;
}
for(int n=1; n<tokens.Length;n++)
lbChatters.Items.Add(tokens[n].Trim(new char[]{'\r','\n'}));
this.Text = clientName + ":已连接到服务器";
}
catch (Exception)
{
MessageBox.Show("注册时发生错误!","错误", MessageBoxButtons.OK, MessageBoxIcon.Exclamation);
}
}
在此之后,当然就是用户之间的聊天了,由ReceiveChat()函数来完成。该函数是一个独立的线程,它处理所有用户获得的消息和用户发送的消息。它主要处理了CHAT、PRIV、JOIN、GONE、QUIT等命令,处理的方法和服务器端的类似。
ReceiveChat()函数实现如下:
private void ReceiveChat()
{
bool keepAlive = true;
while (keepAlive)
{
try
{
Byte[] buffer = new Byte[2048];
ns.Read(buffer,0,buffer.Length);
string chatter = System.Text.Encoding.ASCII.GetString(buffer);
string[] tokens = chatter.Split(new Char[]{'|'});
if (tokens[0] == "CHAT")
{
rtbChatIn.AppendText(tokens[1]);
if(logging)
logwriter.WriteLine(tokens[1]);
}
if (tokens[0] == "PRIV")
{
rtbChatIn.AppendText("Private from ");
rtbChatIn.AppendText(tokens[1].Trim() );
rtbChatIn.AppendText(tokens[2] + "\r\n");
if(logging)
{
logwriter.Write("Private from ");
logwriter.Write(tokens[1].Trim() );
logwriter.WriteLine(tokens[2] + "\r\n");
}
}
if (tokens[0] == "JOIN")
{
rtbChatIn.AppendText(tokens[1].Trim() );
rtbChatIn.AppendText(" has joined the Chat\r\n");
if(logging)
{
logwriter.WriteLine(tokens[1]+" has joined the Chat");
}
string newguy = tokens[1].Trim(new char[]{'\r','\n'});
lbChatters.Items.Add(newguy);
}
if (tokens[0] == "GONE")
{
rtbChatIn.AppendText(tokens[1].Trim() );
rtbChatIn.AppendText(" has left the Chat\r\n");
if(logging)
{
logwriter.WriteLine(tokens[1]+" has left the Chat");
}
lbChatters.Items.Remove(tokens[1].Trim(new char[]{'\r','\n'}));
}
if (tokens[0] == "QUIT")
{
ns.Close();
clientSocket.Close();
keepAlive = false;
StatusBar1.Text = "服务器端已停止";
connected= false;
btnSend.Enabled = false;
btnCloseConnection.Enabled = false;
}
}
catch(Exception){}
}
}
通过以上的一些函数,客户端程序之间就可以进行自由地聊天了,各个用户之间还可以互相发送悄悄话。所以程序已经实现了聊天室的基本功能了,不过最后各个用户还要正常地退出,那就要用到QuitChat()函数了。
QuitChat()函数的具体实现如下:
private void QuitChat()
{
if(connected)
{
try
{
string command = "GONE|" + clientName;
Byte[] outBytes = System.Text.Encoding.ASCII.GetBytes(command.ToCharArray());
ns.Write(outbytes,0,outbytes.Length);
clientSocket.Close();
}
catch(Exception)
{
}
}
if(logging)
logwriter.Close();
if(receive != null && receive.IsAlive)
receive.Abort();
this.Text = "客户端";
}
到此为止,客户端程序的主要部分都已经介绍完毕。
![](https://img2024.cnblogs.com/blog/35695/202408/35695-20240826070647288-243310440.jpg)