public int Xoa(int mataptin)
 {
     try
     {
         LinQDataContext db = new LinQDataContext(global::DAOAuction.Properties.Settings.Default.webdoantruongConnectionString);
     db.TAPTINBAIVIET_delete(mataptin);
     db.SubmitChanges();
     return 0;
     }
     catch (Exception ex)
     {
         throw (ex);
     }
 }