Visual Studio 2010 - Chart control

private void button1_Click(object sender, EventArgs e)
        {
            chart1.Series.Clear();

            string test ="" ,test2 = "",test3 = "";
            datatb2 = new DataTable();

            int index = 0;

            foreach (DataGridViewRow row in dataGridView1.Rows)
            {
                if (row.Cells[1].Value != null && (bool)row.Cells[1].FormattedValue)
                {
                    String idtoselect = row.Cells[0].Value.ToString();
                    try
                    {
                        string sql2 = "select NAME_Product,Unit.NAME_Unit from Product,unit  where Product.ID_Unit = Unit.ID_Unit AND Product.ID_Product = '" + idtoselect + "' ";
                        SqlCommand testcommand2 = new SqlCommand(sql2, conn);
                        rdr = testcommand2.ExecuteReader();
                        if (rdr.Read())
                        {
                            test = rdr["NAME_Product"].ToString();
                            test2 = rdr["NAME_Unit"].ToString();
                        }
                        rdr.Close();
                        test3 = test +"("+ test2+")";

                        try
                        {
                            string sql = "SELECT Product.NAME_Product AS test1, SUM(Reproduct.QUANTITY_Reproduct) AS quan1, CONVERT(VARCHAR(10), Reproduct.DATE_Reproduct, 103) AS Expr1 FROM  Reproduct INNER JOIN Product ON Reproduct.ID_Product = Product.ID_Product where Reproduct.ID_Product = @ID AND Reproduct.ID_Product = Product.ID_Product  AND DATE_Reproduct BETWEEN @D1 AND @D2 GROUP BY Reproduct.ID_Product,Product.ID_Product, Product.NAME_Product, Reproduct.DATE_Reproduct";
                            da = new SqlDataAdapter(sql, conn);

                            da.SelectCommand.Parameters.AddWithValue("@ID", idtoselect);
                            da.SelectCommand.Parameters.AddWithValue("@D1", startDate.Value);
                            da.SelectCommand.Parameters.AddWithValue("@D2", finDate.Value);

                            datatb = new DataTable();

                            da.Fill(datatb);
                            da.Fill(datatb2);


                            //chart1.ChartAreas["ChartArea1"].Area3DStyle.Enable3D = true;
                            chart1.Series.Add(test3);
                            for (int i = 0; i < datatb.Rows.Count; i++)
                            { 
                                chart1.Series[test3].Points.AddXY(datatb.Rows[i].ItemArray.GetValue(0), datatb.Rows[i].ItemArray.GetValue(1));
                            }
                            
                            chart1.Series[test3].ChartArea = "ChartArea1";
                            chart1.Series[test3].BorderWidth = 2;
                            chart1.Series[test3].ChartType = System.Windows.Forms.DataVisualization.Charting.SeriesChartType.Column;
                            chart1.Series[test3].YValueMembers = "quan1";
                            chart1.Series[test3].XValueMember = "test1";
                            chart1.ChartAreas["ChartArea1"].AxisX.LabelStyle.Enabled = false;



                        }
                        catch (Exception ex)
                        {
                            MessageBox.Show("test :" + ex);
                        }

                    }
                    catch
                    {
                        MessageBox.Show("Exception");
                    }


                }
            }

            chart1.DataBind();
            dataGridView2.DataSource = datatb2;
            setdatagrid2();
        }