The session is not available in the ASPX constructor, and you need to rewrite a method to put it in load to use the session normally.

1. Construct a function that inherits System.Web.UI.Page

   <summary>///    brand's constructor///    </summary> public    class CBrandBaseBage:System.Web.UI.Page    {       protected string brandid;       Public Cbrandbasebage ()       {            //showpage (); ShowPage for subclasses, if the subclass uses session[""]= "" will prompt the page missing HttpModule statues            //this. Init + = new EventHandler (Page_Init);             This. Load + = new EventHandler (basepage_load);        }       private void Basepage_load (object sender, EventArgs e)       {           showpage ();//showpage must be placed in Load to use session normally           //To determine the existence of the brand Brandid                  }       Throws a method to subclass rewrite       protected virtual void ShowPage ()       {           //virtual method code       }

2. Child page Inheritance

The parent virtual method that executes        protected override void ShowPage ()        {//base before init            . ShowPage ();            id = function.sqlfilter (dtrequest.getqueryint ("id", 0). ToString ());            if (Id = = "0") return;            if (string. IsNullOrEmpty (Id)) return;            if (System.Web.HttpContext.Current = = null) return;            httpcontext.current.session["bid"] = Id;            HttpContext.Current.Session.Timeout =;            Function.writecookie ("Bid", "ZT", Id);        }

　　

The session is not available in the ASPX constructor, and you need to rewrite a method to put it in load to use the session normally.