//Sửa phòng
 public int updatePhong(PhongDTO pDTO)
 {
     try
     {
         var querry = (from p in htDataContext.phongs
                       where p.maphong == pDTO.Maphong
                       select p).FirstOrDefault<phong>();
         querry.maloai = pDTO.Maloai;
         querry.dadat = pDTO.Dadat;
         querry.danhan = pDTO.Danhan;
         htDataContext.SubmitChanges();
         return 1;
     }
     catch
     {
         return 0;
     }
 }
 //Thêm phòng
 public int insertPhong(PhongDTO pDTO)
 {
     try
     {
         phong p = new phong();
         p.maphong = pDTO.Maphong;
         p.maloai = pDTO.Maloai;
         p.dadat = (bool)pDTO.Dadat;
         p.danhan = (bool)pDTO.Danhan;
         htDataContext.phongs.InsertOnSubmit(p);
         htDataContext.SubmitChanges();
         return 1;
     }
     catch
     {
         return 0;
     }
 }