CSPosAPI.MainForm.buttonAdd_Click C# (CSharp) Method

        private void buttonAdd_Click(object sender, EventArgs e)
        {
            if (comboBoxStock.SelectedItem != null)
            {
                var stock = GetItemById(comboBoxStock.SelectedItem.ToString());
                DataGridViewRow row = (DataGridViewRow)dataGridViewStocks.Rows[0].Clone();
                row.Cells[0].Value = stock.code;
                row.Cells[1].Value = stock.name;
                row.Cells[2].Value = stock.measureUnit;
                row.Cells[3].Value = stock.qty;
                row.Cells[4].Value = stock.unitPrice;
                row.Cells[5].Value = (Convert.ToDouble(stock.unitPrice) * Convert.ToDouble(stock.qty)).ToString();
                row.Cells[6].Value = stock.totalAmount;
                row.Cells[7].Value = stock.vat;
                row.Cells[8].Value = stock.barCode;
                row.Cells[9].Value = stock.cityTax;
                this.dataGridViewStocks.Rows.Add(row);
                Calculate();
                Calculate();
            }
        }