private void LamMoiTopping(bool state = true)
 {
     txtMaTopping.Text            = ToppingBUS.LayMaToppingMoiNhat() + 1 + "";
     txtTenTopping.Text           = txtGiaTienTopping.Text = string.Empty;
     cmbLoaiTopping.SelectedIndex = 0;
     picHinhTopping.Image         = Properties.Resources.default_product;
     btnThemTopping.Enabled       = state;
     btnXoaTopping.Enabled        = !state;
     btnSuaTopping.Enabled        = !state;
     btnKhoiPhucTopping.Enabled   = !state;
     openFileDialog2.FileName     = "";
 }
        private void btnThemTopping_Click(object sender, EventArgs e)
        {
            if (txtTenTopping.Text == "")
            {
                MessageBox.Show("Vui lòng nhập đủ thông tin!", "Thông báo", MessageBoxButtons.OK, MessageBoxIcon.Stop);
                return;
            }
            ToppingDTO topping = new ToppingDTO();

            topping.TenTopping  = txtTenTopping.Text;
            topping.LoaiTopping = Convert.ToInt32(cmbLoaiTopping.SelectedValue);
            if (txtGiaTienTopping.Text != "")
            {
                topping.GiaTien = Convert.ToDouble(txtGiaTienTopping.Text);
            }
            else
            {
                topping.GiaTien = 0;
            }
            if (openFileDialog2.FileName != "")
            {
                string tenFile   = DateTime.Now.ToFileTime() + "_" + (ToppingBUS.LayMaToppingMoiNhat() + 1).ToString();
                string extension = Path.GetExtension(openFileDialog2.SafeFileName);
                topping.Hinh = tenFile + extension;
                File.Copy(openFileDialog2.FileName, "img\\toppings\\" + tenFile + extension, true);
            }
            topping.TrangThai = true;

            if (ToppingBUS.ThemTopping(topping))
            {
                MessageBox.Show("Thêm thành công!", "Thông báo", MessageBoxButtons.OK, MessageBoxIcon.Information);
                LamMoiTopping();
                QLTP_LoadDanhSachTopping(GetTimKiemTopping(), Convert.ToInt32(cmbTimKiemTheoLoaiTopping.SelectedValue));
                dgvTopping.ClearSelection();
            }
            else
            {
                MessageBox.Show("Thêm thất bại!", "Thông báo", MessageBoxButtons.OK, MessageBoxIcon.Error);
                topping = null;
            }
        }