public DataTable laySach()// { return(dalsach.laySach()); }
public DataTable laySach(int idsach) { return(dalsach.laySach(idsach)); }
public DataTable laySach()// { return(dalsach.laySach()); }
public DataTable laySach(int idsach) { return(dalsach.laySach(idsach)); }