Yesterday Mudassar and Azim gave replied to the question
http://www.aspforums.net/Threads/968618/How-to-programatically-reset-the-session-time-without-page-refreshing-in-ASPNet/
and solved it ,
now i want to ask that if i have 3 content pages and 1 master page , e.g.
1 - Site.master
2 - DailyLog.aspx
3 - ProjectMaker.aspx
4 - ProjectProfile.aspx
so adding this c# coding :
protected void Page_Load(object sender, EventArgs e)
{
    Session["Name"] = "Mudassar";
    Configuration config = WebConfigurationManager.OpenWebConfiguration("~/Web.Config");
    SessionStateSection section = (SessionStateSection)config.GetSection("system.web/sessionState");
    int timeout = (int)section.Timeout.TotalMinutes * 1000 * 60;
    ClientScript.RegisterStartupScript(this.GetType(), "SessionAlert", "SessionExpireAlert(" + timeout + ");", true);
 
}
 
[System.Web.Services.WebMethod(EnableSession = true)]
public static int RefreshSession()
{
    HttpContext.Current.Session["Name"] = "Mudassar";
    Configuration config = WebConfigurationManager.OpenWebConfiguration("~/Web.Config");
    SessionStateSection section = (SessionStateSection)config.GetSection("system.web/sessionState");
    int timeout = (int)section.Timeout.TotalMinutes * 1000 * 60;
    return timeout;
}
 
protected void ResetSession(object sender, EventArgs e)
{
    string name = Session["Name"].ToString();
}
to only DailyLog.aspx , is sufficient for all pages ? because i want to show alert on every page ... Or do i have to insert the above c# code in all the content pages ?