//xoa khu vuc
 public static bool XoaBoPhan(string maKhuVuc)
 {
     return(DL_BoPhan.BoPhanXoa(maKhuVuc));
 }
 //them
 public static bool ThemBoPhan(string ma, string ten)
 {
     return(DL_BoPhan.BoPhanThem(ma, ten));
 }
 //sua
 public static bool SuaBoPhan(string ma, string ten)
 {
     return(DL_BoPhan.BoPhanSua(ma, ten));
 }
 public static DataTable LayDuLieuBoPhan()
 {
     return(DL_BoPhan.DuLieuBoPhan());
 }