VS2005下实现asp.net在线人数的统计

 首先在项目中选择“添加新项”，添加“Global.asax”全局变量文件
using System;
using System.Collections;
using System.ComponentModel;
using System.Web;
using System.Web.SessionState;
using System.IO ;
namespace movie
{
/// <summary>
/// Global 的摘要说明。
/// </summary>
public class Global : System.Web.HttpApplication
{
  /// <summary>
  /// 必需的设计器变量。
  /// </summary>
  private System.ComponentModel.IContainer components = null;
  public Global()
  {
    InitializeComponent();
  }
 
  protected void Application_Start(Object sender, EventArgs e)
  {
            Application["conn"]="Server=localhost;database=movie;uid=sa;pwd='zcc';";
    Application["user_sessions"] = 0;
    Application["counter_num"]=0;
    uint 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=UInt32.Parse (str);
    }
    object obj=count;
    Application["counter"]=obj;
    srd.Close ();
  }
  protected void Session_Start(Object sender, EventArgs e)
  {
    Application.Lock();
    Application["user_sessions"] = (int)Application["user_sessions"] + 1;
    Application.UnLock();
    Application.Lock ();
    //数值累加，注意这里使用了装箱（boxing）
    uint jishu=0;
    jishu=(uint)Application["counter"];
    jishu=jishu+1;
    object obj=jishu;
    Application["counter"]=obj;
    //将数据记录写入文件