Web Development

void Application_Start(object sender, EventArgs e)

{
    Application["ActiveSessions"] = 0;

}

void Session_Start(object sender, EventArgs e)

{
    try
    {
        Application.Lock();


        int activeSessions = (int) Application["ActiveSessions"] + 1;

        int allowedSessions = 10; // retrieve the threshold here instead


        Application["ActiveSessions"] = activeSessions;


        if (activeSessions > allowedSessions)

                System.Web.HttpContext.Current.Response.Redirect("~/UserLimitReached.aspx", false);

    }
    finally
    {
        Application.UnLock();

    }
}

void Session_End(object sender, EventArgs e)

{
    Application.Lock();
    Application["ActiveSessions"] = (int)Application["ActiveSessions"] - 1;

    Application.UnLock();
}