NHibernate分页

   public  IList < Orders >  GetUserOrderByUserID( string  userid,  int  PageIndex,  int  PageSize,  out   long  count)
        {
             using  (ISession _session  =   base .GetSession())
            {
                var hql  =   " select count(*) from Orders where userid=:userid " ;
                IQuery query  =  _session.CreateQuery(hql);
                query.SetString( " userid " , userid);
                 object  obj  =  query.UniqueResult();
                 long .TryParse(obj.ToString(),  out  count);


                var list  =  from p  in  _session.Linq < Orders > ()
                   .Where(p  =>  p.UserID  ==  userid)
                   .OrderByDescending(p  =>  p.Otime)
                   .Skip((PageIndex  -   1 )  *  PageSize)
                   .Take(PageSize)
                           select p;

                 return  list.ToList < Orders > ();
            }
        }