最好是绑定数据库的方法

建立一个Global.asax里面代码如下：
<%@ Application Language="C#" %>
<%@ Import Namespace=" %>
<%@ Import Namespace="System.Data" %>

<script runat="server">

    void Application_Start(object sender, EventArgs e)
    {
        Application["UsersOnline"] = 0;
        int count = 0;
        StreamReader srd;
        //取得文件的实际路径
        string file_path = Server.MapPath("counter.txt");
        //打开文件进行读取
        srd = File.OpenText(file_path);
        while (srd.Peek() != -1)
        {
            string str = srd.ReadLine();
            count = Int32.Parse(str);
        }
        object obj = count;
        Application["TotalCount"] = obj;
        srd.Close();
    }
   
    void Application_End(object sender, EventArgs e)
    {
        int count = 0;
        count = (int)Application["TotalCount"];
        string file_path = Server.MapPath("counter.txt");
        StreamWriter fs = new StreamWriter(file_path, false);
        fs.WriteLine(count);
        fs.Close();

        //DataSet objDataSet = new DataSet();
        //objDataSet.ReadXml(Server.MapPath("count.xml"));
        //int maxCount = Convert.ToInt32(objDataSet.Tables["MyCount"].Rows[0]["MaxCount"]);
        //Application["MaxCount"] = maxCount;
        //if (maxCount < (int)Application["UsersOnline"])    //如果MaxCount标签里面的值小于当前在线人数的值，就存入
        //    objDataSet.Tables["MyCount"].Rows[0]["MaxCount"] = (int)Application["UsersOnline"];
        //objDataSet.WriteXml(Server.MapPath("count.xml"));
    }
        
    void Application_Error(object sender, EventArgs e)
    {
        // 在出现未处理的错误时运行的代码

    }

    void Session_Start(object sender, EventArgs e)
    {
        Application.Lock();
        Application["UsersOnline"] = (int)Application["UsersOnline"] + 1;

        StreamReader srd;
        int maxCount = 0;
        //取得文件的实际路径
        string file_pathm = Server.MapPath("max.txt");
        //打开文件进行读取
        srd = File.OpenText(file_pathm);
        while (srd.Peek() != -1)
        {
            string str = srd.ReadLine();
            maxCount = Int32.Parse(str);
        }
        srd.Close();
        if (maxCount < (int)Application["UsersOnline"])
            maxCount = (int)Application["UsersOnline"];
        string max_file_path = Server.MapPath("max.txt");
        StreamWriter max_fs = new StreamWriter(max_file_path, false);
        max_fs.WriteLine(maxCount);
        max_fs.Close();
        
        //访问总数加1
        int count = 0;
        count = (int)Application["TotalCount"];
        count = count + 1;
        Application["TotalCount"] = count;
        //将数据记录写入文件
        string file_path = Server.MapPath("counter.txt");
        try
        {
            StreamWriter fs = new StreamWriter(file_path, false);
            fs.WriteLine(count);
            fs.Close();
        }
        catch (Exception ex)
        {
            Application["Error"] = ex.Message;
        }
        Application.UnLock();
    }

    void Session_End(object sender, EventArgs e)
    {
        Application["UsersOnline"] = (int)Application["UsersOnline"] - 1;
        Application.UnLock();
    }
      
</script>
使用时：
 protected void Page_Load(object sender, EventArgs e)
    {
        if (Application["UsersOnline"] != null)
        {
            currentUserNum.Text = Application["UsersOnline"].ToString();
        }
        if (Application["TotalCount"] != null)
        {
            totalUserNum.Text = Application["TotalCount"].ToString();
        }
        if (Application["UsersOnline"] != null)
        {
            StreamReader srd;
            int maxCount = 0;
            //取得文件的实际路径
            string file_path = Server.MapPath("max.txt");
            //打开文件进行读取
            srd = File.OpenText(file_path);
            while (srd.Peek() != -1)
            {
                string str = srd.ReadLine();
                maxCount = Int32.Parse(str);
            }
            srd.Close();
            if (maxCount < int.Parse(Application["UsersOnline"].ToString()))
                maxCount = int.Parse(Application["UsersOnline"].ToString());
            maxUserNum.Text = maxCount.ToString();
        }
根据需要建txt文件

真好啊， 我去尝试下

嗯,不错,学习中^

好东西

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