public int get_page_total_of_khoa()
 {
     Khoa_ctrl temp = new Khoa_ctrl();
     return temp.page_total_khoa;
 }
 public Result<bool> insertKhoa(string ma, string ten, string dc, string dthoai)
 {
     Khoa_ctrl temp = new Khoa_ctrl();
     return temp.insert_khoa(new Khoa_ett(ma, ten, dc, dthoai));
 }
 public Result<bool> editKhoa(string ma, string ten, string dc, string dthoai)
 {
     Khoa_ctrl temp = new Khoa_ctrl();
     return temp.edit_khoa(ma, ten, dc, dthoai);
 }
 public Result<bool> deleteKhoa(string ma)
 {
     Khoa_ctrl temp = new Khoa_ctrl();
     return temp.delete_khoa(ma);
 }
 public Result<List<Khoa_ett>> selectByPagingKhoa(int current_page)
 {
     Khoa_ctrl temp = new Khoa_ctrl();
     return temp.select_by_paging_khoa(current_page);
 }
 public Result<List<Khoa_ett>> selectByFieldsKhoa(string inputName, string how)
 {
     Khoa_ctrl temp = new Khoa_ctrl();
     return temp.select_by_fields(inputName, how);
 }
 public Result<List<Khoa_ett>> selectAllKhoa()
 {
     Khoa_ctrl temp = new Khoa_ctrl();
     return temp.select_all_khoa();
 }