cache 解决在线用户方案

来源：互联网发布：套利算法交易编辑：程序博客网时间：2024/05/04 06:15

在线用户的统计方法有很多其中一个就是SESSION保存在数据库,然后select tmpdb表,获取在线用户. 下面介绍一个非常有用的办法试用Cache, Cache是服务器的方法,跟ASP的Application差不多, 下面是一个Cache在线用户的超作, 流程:建立一个DataTable 把需要的字段添加进去, id,userid,username,place,lasttime lasttime是最后活动的时间,这个时间是决定用户是否超时登陆,然后用一个方法来删除过时的用户

using System;

using System.Data;

using System.Configuration;

using System.Web;

using System.Web.Caching;

using System.Web.Security;

using System.Web.UI;

using System.Web.UI.WebControls;

using System.Web.UI.WebControls.WebParts;

using System.Web.UI.HtmlControls;

/// <summary>
/// OnlineCache 的摘要说明
/// </summary>
public class OnlineCache
{
public OnlineCache()
{
}
#region 缓存在线用户
/// <summary>
/// 建立缓存表
/// </summary>
public static void BuildCacheOnlineTable()
{
DataTable dt = new DataTable();
DataColumn col1 = dt.Columns.Add("ID", typeof(Int32));
col1.AllowDBNull = false;
col1.AutoIncrement = true;
col1.AutoIncrementSeed = 1;
col1.AutoIncrementStep = 1;
col1.Unique = true;
DataColumn col2 = dt.Columns.Add("UserID", typeof(String));
col2.AllowDBNull = true;
DataColumn col3 = dt.Columns.Add("UserName", typeof(String));
col3.AllowDBNull = true;
DataColumn col4 = dt.Columns.Add("UserPlace", typeof(String));
col4.AllowDBNull = true;
DataColumn col5 = dt.Columns.Add("IP", typeof(String));
col5.AllowDBNull = true;
DataColumn col6 = dt.Columns.Add("LastActiveTime", typeof(DateTime));
col6.AllowDBNull = true;
col6.DefaultValue = DateTime.Now;
HttpContext.Current.Cache.Add("UserOnlineTable", dt, null, DateTime.Now.AddYears(10), TimeSpan.Zero, CacheItemPriority.Normal, null);
}
/// <summary>
/// 获取当前位置
/// </summary>
/// <returns></returns>
public static string GetPlace()
{
string str = "首页";
if (HttpContext.Current.Request.Url != null)
{
string url = HttpContext.Current.Request.Url.AbsolutePath.ToLower();
if (url.IndexOf("default.aspx") >= 0)
{
str = "首页";
}
else if (url.IndexOf("detail.aspx") >= 0)
{
str = "查看详细";
}
else if (url.IndexOf("getpassword.aspx") >= 0)
{
str = "取回密码";
}
else if (url.IndexOf("gettry.aspx") >= 0)
{
str = "获取试用";
}
else if (url.IndexOf("gopay.aspx") >= 0)
{
str = "付款";
}
else if (url.IndexOf("modpass.aspx") >= 0)
{
str = "修改密码";
}
else if (url.IndexOf("modprofile.aspx") >= 0)
{
str = "修改资料";
}
else if (url.IndexOf("myorder.aspx") >= 0)
{
str = "我的订单";
}
else if (url.IndexOf("myreport.aspx") >= 0)
{
str = "我的报告";
}
else if (url.IndexOf("register.aspx") >= 0)
{
str = "注册";
}
else if (url.IndexOf("writereport.aspx") >= 0)
{
str = "写报告";
}
else if (url.IndexOf("forumlist.aspx") >= 0)
{
str = "论坛列表";
}
else if (url.IndexOf("forummail.aspx") >= 0)
{
str = "论坛邮箱";
}
else if (url.IndexOf("forumsetsign.aspx") >= 0)
{
str = "修改个人签名";
}
else if (url.IndexOf("forumtopic.aspx") >= 0)
{
str = "浏览贴子";
}
else if (url.IndexOf("forum.aspx") >= 0)
{
str = "论坛首页";
}
else if (url.IndexOf("list.aspx") >= 0)
{
str = "查看类别";
}
}
return str;
}
/// <summary>
/// 统计在线人数
/// </summary>
/// <returns></returns>
public static int OnlineCount()
{
if (HttpContext.Current.Cache["UserOnlineTable"] == null)
BuildCacheOnlineTable();
DataTable dt = (DataTable)HttpContext.Current.Cache["UserOnlineTable"];
return dt.Rows.Count;
}
/// <summary>
/// 获取在线用户列表
/// </summary>
/// <returns></returns>
public static DataTable GetOnlineUserTable()
{
ClearExptionUser();
return (DataTable)HttpContext.Current.Cache["UserOnlineTable"];
}
/// <summary>
/// 检查IP是否在Cache中
/// </summary>
/// <param name="ip"></param>
/// <returns></returns>
public static bool CheckOnlineIP(string ip)
{
if (HttpContext.Current.Cache["UserOnlineTable"] == null)
BuildCacheOnlineTable();
DataTable dt = (DataTable)HttpContext.Current.Cache["UserOnlineTable"];
DataRow[] drs = dt.Select("ip='" + ip + "'");
bool result = false;
if (drs.Length > 0)
result = true;
return result;
}
/// <summary>
/// 用户是否在线
/// </summary>
/// <param name="userid"></param>
/// <returns></returns>
public static bool IsOnline(string userid)
{
if (HttpContext.Current.Cache["UserOnlineTable"] == null)
BuildCacheOnlineTable();
DataTable dt = (DataTable)HttpContext.Current.Cache["UserOnlineTable"];
DataRow[] drs = dt.Select("userid='" + userid + "'");
bool result = false;
if (drs.Length > 0)
result = true;
return result;
}
/// <summary>
/// 删除过时用户
/// </summary>
public static void ClearExptionUser()
{
if (HttpContext.Current.Cache["UserOnlineTable"] == null)
BuildCacheOnlineTable();
DataTable dt = (DataTable)HttpContext.Current.Cache["UserOnlineTable"];
for (int i = 0; i < dt.Rows.Count; i++)
{
DateTime lastactive = Convert.ToDateTime(dt.Rows[i]["LastActiveTime"]);
int diff = Convert.ToInt32(Unit.DateDiff("minute", lastactive, DateTime.Now));
if (diff > 20)
{
dt.Rows[i].Delete();
}
}
HttpContext.Current.Cache.Add("UserOnlineTable", dt, null, DateTime.Now.AddYears(10), TimeSpan.Zero, CacheItemPriority.Normal, null);
}
/// <summary>
/// 更新用户活动时间
/// </summary>
/// <param name="userid"></param>
public static void UpdateOnline(string userid, string place)
{
if (HttpContext.Current.Cache["UserOnlineTable"] == null)
BuildCacheOnlineTable();
DataTable dt = (DataTable)HttpContext.Current.Cache["UserOnlineTable"];
DataRow[] drs = dt.Select("userid='" + userid + "'");
for (int i = 0; i < drs.Length; i++)
{
drs[i]["LastActiveTime"] = DateTime.Now;
drs[i]["UserPlace"] = place;
}
HttpContext.Current.Cache.Add("UserOnlineTable", dt, null, DateTime.Now.AddYears(10), TimeSpan.Zero, CacheItemPriority.Normal, null);
}
public static void UpdateOnlineByIP(string userid, string username, string userplace, string ip)
{
if (HttpContext.Current.Cache["UserOnlineTable"] == null)
BuildCacheOnlineTable();
DataTable dt = (DataTable)HttpContext.Current.Cache["UserOnlineTable"];
DataRow[] drs = dt.Select("ip='" + ip + "'");
for (int i = 0; i < drs.Length; i++)
{
drs[i]["LastActiveTime"] = DateTime.Now;
drs[i]["UserID"] = userid;
drs[i]["UserName"] = username;
drs[i]["UserPlace"] = userplace;
}
HttpContext.Current.Cache.Add("UserOnlineTable", dt, null, DateTime.Now.AddYears(10), TimeSpan.Zero, CacheItemPriority.Normal, null);
}
public static void DeleteOnlineUser(string userid)
{
if (HttpContext.Current.Cache["UserOnlineTable"] == null)
BuildCacheOnlineTable();
DataTable dt = (DataTable)HttpContext.Current.Cache["UserOnlineTable"];
DataRow[] drs = dt.Select("userid='" + userid + "'");
for (int i = 0; i < drs.Length; i++)
{
dt.Rows.Remove(drs[i]);
}
HttpContext.Current.Cache.Add("UserOnlineTable", dt, null, DateTime.Now.AddYears(10), TimeSpan.Zero, CacheItemPriority.Normal, null);
}
public static void InsertOnlineUser(string userid, string username, string UserPlace, string IP)
{
if (HttpContext.Current.Cache["UserOnlineTable"] == null)
BuildCacheOnlineTable();
DataTable dt = (DataTable)HttpContext.Current.Cache["UserOnlineTable"];
DataRow workRow;
workRow = dt.NewRow();
workRow["UserID"] = userid;
workRow["UserName"] = username;
workRow["UserPlace"] = UserPlace;
workRow["IP"] = IP;
workRow["LastActiveTime"] = DateTime.Now;
dt.Rows.Add(workRow);
HttpContext.Current.Cache.Add("UserOnlineTable", dt, null, DateTime.Now.AddYears(10), TimeSpan.Zero, CacheItemPriority.Normal, null);
ClearExptionUser();
}
#endregion
}