private void btSua_Click(object sender, EventArgs e) { DTO_DanhMucSanPham sp = new DTO_DanhMucSanPham(tbTen.Text); sp.ID = id; DAO_DanhMucSanPham dao = new DAO_DanhMucSanPham(); if (id != 0) { if (ex.KiemTraChuoi(sp.Tendanhmuc, 100)) { dao.Update(sp); } else { MessageBox.Show("Name very long"); } } else { } FDanhMucSanPham_Load(sender, e); }