private void btnSua_Click(object sender, EventArgs e)
        {
            FrmSuaSach suasach = new FrmSuaSach(XoaMa);

            suasach.ShowDialog();
            dgvDausach.DataSource = Sach_DAO.TimKiem("");
        }
        private void btnTim_Click(object sender, EventArgs e)
        {
            string dk;

            if (cboDanhmuc.SelectedItem.ToString() == "Tên sách")
            {
                dk = txtTim.Text.ToString();
                dgvDausach.DataSource = Sach_DAO.TimKiem("where TenSach like N'%" + dk.Trim() + "%'");
            }
            if (cboDanhmuc.SelectedItem.ToString() == "Chủ đề")
            {
                dk = txtTim.Text.ToString();
                dgvDausach.DataSource = Sach_DAO.TimKiem("where TenCD like N'%" + dk.Trim() + "%'");
            }
            if (cboDanhmuc.SelectedItem.ToString() == "Nhà xuất bản")
            {
                dk = txtTim.Text.ToString();
                dgvDausach.DataSource = Sach_DAO.TimKiem("where TenNXB like N'%" + dk.Trim() + "%'");
            }
            if (cboDanhmuc.SelectedItem.ToString() == "Ngày nhập")
            {
                dk = txtTim.Text.ToString();
                dgvDausach.DataSource = Sach_DAO.TimKiem("where NgayNhap= '" + dk.Trim() + "'");
            }
        }
        private void btnXoa_Click(object sender, EventArgs e)
        {
            Sach_DTO entity = new Sach_DTO();

            entity.MaSach = int.Parse(XoaMa);
            Sach_DAO.Xoa(entity);
            dgvDausach.DataSource = Sach_DAO.TimKiem("");
        }
 private void FrmTimKiemSach_Load(object sender, EventArgs e)
 {
     dgvDausach.DataSource = Sach_DAO.TimKiem("");
 }