C # count the number of online members

Using System;
Using System. Data;
Using System. Configuration;
Using System. Linq;
Using System. Web;
Using System. Web. Security;
Using System. Web. UI;
Using System. Web. UI. HtmlControls;
Using System. Web. UI. WebControls;
Using System. Web. UI. WebControls. WebParts;
Using System. Xml. Linq;
Using System. Text;

/// <Summary>
/// Summary of onlineCount
/// </Summary>
Public class onlineCount
{
Private string USERNAME;
Private int OFFLINEDIFF;
Private int REMOVEDIFF;

Public onlineCount ()
{
// Set or read the configuration parameters directly from the configuration file.
/// Session name that stores the user name
USERNAME = HttpContext. Current. Session ["username"]. ToString ();
/// The number of minutes of inactivity deleted from the online list
/// U
OFFLINEDIFF = 5;
/// How many seconds does one delete a non-active user?
REMOVEDIFF = 10;

If (System. Web. HttpContext. Current. Application ["OnlineTalbe"] = null)
{
This. CashTableInit ();
}
}
Public void checkonline ()
{
// Obtain the data table and sessionid from the application
Datatable dtonline;
Dtonline = (datatable) system. Web. httpcontext. Current. application ["onlinetalbe"];
String sessionid = system. Web. httpcontext. Current. session. sessionid. tostring ();
// System. Web. httpcontext. Current. response. Write (sessionid );

// Check whether my records exist in the data table
Datarow drfind = dtonline. Rows. Find (sessionid );
If (drfind! = NULL)
{
// Yes; update my status
Drfind ["lastactivetime"] = datetime. now;
Drfind ["userwhere"] = This. atwhere;
// The user changes from visitor status to login member, or vice versa
Drfind ["visitorname"] = username;
Drfind ["visitorlevel"] = 1;
}
Else
{
// None; add online information about me
DataRow drNew = dtOnline. NewRow ();
DrNew ["SessionID"] = sessionId;
DrNew ["VisitorName"] = USERNAME;
DrNew ["VisitorLevel"] = 1;
DrNew ["LastActiveTime"] = DateTime. Now;
DrNew ["LoginTime"] = DateTime. Now;
DrNew ["VisitorIP"] = System. Web. HttpContext. Current. Request. UserHostAddress;
DrNew ["UserWhere"] = this. AtWhere;

DtOnline. Rows. Add (drNew );
}
// If no one is performing deletion and the interval between the last deletion exceeds the set value

TimeSpan tsRemove = DateTime. Now-Convert. ToDateTime (GetApplication ("LastRemove "));
If (tsRemove. Seconds> REMOVEDIFF & this. GetApplication ("Removing"). ToString () = "n ")
{
// Locked. I am deleting expired users
System. Web. HttpContext. Current. Application. Lock ();
SetApplication ("Removing", "y ");
System. Web. HttpContext. Current. Application. UnLock ();
// Do not know whether Rows. Count decreases with the cycle. If it is more efficient than foreach, and foreach cannot be used here
For (int I = 0; I <dtOnline. Rows. Count; I ++)
{
DataRow drDel = dtOnline. Rows [I];
TimeSpan ts = DateTime. Now-Convert. ToDateTime (drDel ["LastActiveTime"]);
If (ts. Minutes> OFFLINEDIFF)
{
DtOnline. Rows. Remove (drDel );
System. Web. HttpContext. Current. Response. Write ("tired ");
}
}

System. Web. HttpContext. Current. Application. Lock ();
SetApplication ("Removing", "n ");
SetApplication ("LastRemove", DateTime. Now. ToString ());
System. Web. HttpContext. Current. Application. UnLock ();
}

// Put the data table that has been exhausted into the Application
DtOnline. AcceptChanges ();
System. Web. HttpContext. Current. Application. Lock ();
System. Web. HttpContext. Current. Application ["DataTalbeOnline"] = dtOnline;
System. Web. HttpContext. Current. Application. UnLock ();
}
// Obtain the corresponding value based on apcname
Private string GetApplication (string apcname)
{
Return System. Web. HttpContext. Current. Application [apcname]. ToString ();
}
// Assign a value to the Application
Public void SetApplication (string apcname, string apcvalue)
{

System. Web. HttpContext. Current. Application [apcname] = apcvalue;

}
/// <Summary>
/// Return the current user location
/// </Summary>
Private string AtWhere
{
Get
{
System. Text. StringBuilder sb = new System. Text. StringBuilder ();
Sb. Append (System. Web. HttpContext. Current. Request. ServerVariables ["url"]);
If (System. Web. HttpContext. Current. Request. ServerVariables ["QUERY_STRING"]! = String. Empty)
{
Sb. Append ("? ");
Sb. Append (System. Web. HttpContext. Current. Request. ServerVariables ["QUERY_STRING"]);
}
Return sb. ToString ();
}
}
/// <Summary>
/// Create a table
/// </Summary>
Public void CashTableInit ()
{
DataTable dt = new DataTable ("OnlineTalbe"); // create a temporary table
Dt. Columns. Add ("SessionID", typeof (string ));
Dt. Columns. Add ("VisitorName", typeof (string ));
Dt. Columns. Add ("VisitorLevel", typeof (int ));
Dt. Columns. Add ("LastActiveTime", typeof (DateTime ));
Dt. Columns. Add ("LoginTime", typeof (DateTime ));
Dt. Columns. Add ("VisitorIP", typeof (string ));
Dt. Columns. Add ("UserWhere", typeof (string ));
Dt. Columns ["SessionID"]. Unique = true;
Dt. PrimaryKey = new DataColumn [] {dt. Columns ["SessionID"]};

System. Web. HttpContext. Current. Application ["OnlineTalbe"] = dt;
System. Web. HttpContext. Current. Application ["LastRemove"] = DateTime. Now. ToString ();
System. Web. HttpContext. Current. Application ["Removing"] = "n ";
}
}

 

Add

 

Protected void Page_Load (object sender, EventArgs e)
{

// Online test statistics
OnlineCount oc = new onlineCount ();
Oc. CheckOnline ();

}

 

Add

Protected void Page_Load (object sender, EventArgs e)
{
If (! IsPostBack)
{
If (Application ["OnlineTalbe"]! = Null)
{

BindData ();

}

}

}

Void bindData ()
{
If (Application ["OnlineTalbe"]! = Null)
{
Datatable dt = (datatable) application ["onlinetalbe"];
Datalist1.datasource = DT;
Datalist1.databind ();

Int totalrecord = DT. Rows. count;
Aspnetpager1.recordcount = totalrecord;

DT. Dispose ();
}

}

Protected void aspnetpager1_pagechanged (Object sender, eventargs E)
{

Binddata ();

}