public DataTable GetAll()
 {
     try
     {
         RankingDAL rankingDAL = new RankingDAL();
         return(rankingDAL.GetAll());
     }
     catch (Exception)
     {
         throw;
     }
 }
 public DataTable GetById(int id)
 {
     try
     {
         RankingDAL rankingDAL = new RankingDAL();
         return(rankingDAL.GetById(id));
     }
     catch (Exception)
     {
         throw;
     }
 }
 public bool Delete(Rankings ranking)
 {
     try
     {
         RankingDAL rankingDAL = new RankingDAL();
         return(rankingDAL.Delete(ranking));
     }
     catch (Exception)
     {
         throw;
     }
 }
        public bool Save(Rankings ranking)
        {
            try
            {
                RankingDAL rankingDAL = new RankingDAL();

                if (IsUniversityNameExist(ranking))
                {
                    throw new Exception("University name already exist.");
                }
                else
                {
                    return(rankingDAL.Save(ranking));
                }
            }
            catch (Exception)
            {
                throw;
            }
        }