ASP. NET C # implements real-time user online

 Public Static classuseronline{/// <summary>    ///get or set the online list/// </summary>     Public StaticHashtable onlineuserlist {Get        {            if(httpcontext.current.application["onlineuserlist"] ==NULL) {Hashtable onlineuserlist=NewHashtable (); httpcontext.current.application["onlineuserlist"] =onlineuserlist; }            return(Hashtable) httpcontext.current.application["onlineuserlist"]; }        Set{httpcontext.current.application["onlineuserlist"] =value; }    }    /// <summary>    ///Add online Members/// </summary>     Public Static BOOLOnlineuserlist_add (stringKeystringvalue) {        Try        {            if(Onlineuserlist.contains (key)) Onlineuserlist[key]=value; ElseOnlineuserlist.add (key, value); return true; }        Catch        {            return false; }    }    /// <summary>    ///Add online Members/// </summary>     Public Static BOOLOnlineuserlist_add (stringkey) {        stringValue =DateTime.Now.ToString (); returnOnlineuserlist_add (key, value); }    /// <summary>    ///Delete users offline/// </summary>     Public Static BOOLOnlineuserlist_delete (stringkey) {        BOOLRe =false; if(Onlineuserlist.contains (key)) {Hashtable userlist=onlineuserlist;            Userlist.remove (key); Onlineuserlist=userlist; return true; }        returnre; }    /// <summary>    ///determine if the user is online/// </summary>     Public Static BOOLuserIsOnline (stringadminname)        {onlineclearuserouttimeinonlinelist (); returnOnlineuserlist.contains (adminname)?true:false; }    /// <summary>    ///Delete Timeout online users/// </summary>     Public Static voidonlineclearuserouttimeinonlinelist () {intOnlinetimeout = -; Hashtable List=NewHashtable (); Hashtable temlist=NewHashtable (); List=onlineuserlist; Temlist=NewHashtable (list); foreach(DictionaryEntry deinchtemlist) {            //Delete TimeoutDateTime Onlinetime =Convert.todatetime (DE.            Value); TimeSpan TimeSpan= DateTime.Now-Onlinetime; //Delete online time and current time interval greater than timeout minutes (note: The user illegally closes the browser)            if(Timespan.totalminutes >= (Double) {onlinetimeout) {list. Remove (DE.            Key); }} onlineuserlist=list; }}

ASP. NET C # implements real-time user online