room.cs

征服ASP.NET 2.0 Ajax 典型应用源码

using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Threading;
using System.Collections.Generic;
//聊天室
public class Room
{
    private static readonly long ClearUserInterval = 300000;//调用定时函数的时间间隔5分钟
    private static readonly TimeSpan ExpiringInterval = new TimeSpan(0, 10, 0);//过期的区间10分钟
    private static readonly int MessageLimit = 50;//存储的信息的最大数量
    private Dictionary<string, ChatUser> chatingUsers = null;//聊天用户的集合
    private LinkedList<Msg> chatMessage = null;//消息集合
    private Timer timer = null;
    private object islock = new object();
    public Room()
    {
        this.chatingUsers = new Dictionary<string, ChatUser>();
        this.chatMessage = new LinkedList<Msg>();
        //定期清除过期用户
        TimerCallback callback = new TimerCallback(this.OnClearExpiredUser);
        this.timer = new Timer(callback, null, ClearUserInterval, ClearUserInterval);
    }
    private static Room _Instance = new Room();
    public static Room Instance//singleton设计模式，保证全局只有一个Room实例
    {
        get
        {
            return _Instance;
        }
    }
  
    
    //用户是否在聊天
    public bool UserIsChatting(string userName)
    {
        return this.chatingUsers.ContainsKey(userName);
    }
    //获取特定的聊天用户类
    public ChatUser GetUser(string userName)
    {
        return this.chatingUsers[userName];
    }
    //添加一个聊天用户
    public void AddUser(string userName, string password)
    {
        lock (islock)//上锁
        {
            this.chatingUsers[userName] = new ChatUser(userName, password);
        }
    }
    //定期执行的函数，踢掉过期用户
    private void OnClearExpiredUser(object state)
    {
        lock (islock)//防止并发
        {
            List<ChatUser> expiredUsers = new List<ChatUser>();//过期用户
            foreach (ChatUser user in this.chatingUsers.Values)//遍历所有用户，找出过期用户
            {
                if (user.IsExpired(ExpiringInterval))
                {
                    expiredUsers.Add(user);
                }
            }
            //踢出过期用户
            foreach (ChatUser user in expiredUsers)
            {
                this.chatingUsers.Remove(user.Name);
            }
        }
    }
    //发送消息
    public void SendMessage(string userName, string othername, string message, string isbold, string color, string img)
    {
        lock (islock)
        {
            if (this.chatMessage.Count >= MessageLimit)//信息量超出最大值，清除一个
            {
                this.chatMessage.RemoveFirst();
            }
            //添加新信息
            this.chatMessage.AddLast(new Msg(userName, othername, message, isbold, color, img));
        }
    }
    public void SendMessage(string message)//发送系统消息
    {
        lock (islock)
        {
            if (this.chatMessage.Count >= MessageLimit)
            {
                this.chatMessage.RemoveFirst();
            }
            //添加消息
            this.chatMessage.AddLast(new Msg(message));
        }
    }
    //所有消息
    public IEnumerable<Msg> GetAllMessages()
    {
        return this.chatMessage;
    }
    //所有用户
    public IEnumerable<ChatUser> GetAllUsers()
    {
        return this.chatingUsers.Values;
    }
}