public static void DoLogin(System.Web.HttpRequest Request, _
  System.Web.SessionState.HttpSessionState Session, System.Web.HttpResponse _
  Response)
{
......
}

public static bool CheckLogin(System.Web.HttpRequest Request, _
  System.Web.SessionState.HttpSessionState Session, System.Web.HttpResponse _
  Response)
{
.....
}

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
 
namespace _PROJEKT.Views.Shared
{
    public partial class MainMasterPage : System.Web.UI.MasterPage
    {
        protected void Page_Load(object sender, EventArgs e)
        {
            if (Request.Form["UserLogin"] == "login")
            {
                _PROJEKT.MvcApplication.DoLogin(Request,Session,Response );
            }
        }   
    }
}

Session["UserId"] = UserId;