Chart type selection from Dropdown and Adding new Series from Code behind using dot net 4.0

Design Code:

<asp:DropDownList ID="DropDownList1" runat="server"

onselectedindexchanged="DropDownList1_SelectedIndexChanged" AutoPostBack="true">

<asp:ListItem Selected="True">Select</asp:ListItem>

<asp:ListItem Value="Line">Line Chart</asp:ListItem>

<asp:ListItem Value="Area">Area Chart</asp:ListItem>

</asp:DropDownList>

<asp:Chart ID="Chart1" runat="server">

<Series>

<asp:Series Name="Series1">

</asp:Series>

</Series>

<ChartAreas>

<asp:ChartArea Name="ChartArea1">

</asp:ChartArea>

</ChartAreas>

</asp:Chart>

C# Code:

using System;

using System.Collections.Generic;

using System.Linq;

using System.Web;

using System.Web.UI;

using System.Web.UI.WebControls;

using System.Web.UI.DataVisualization.Charting;

using System.Data;

using System.Data.SqlClient;

using System.Configuration;

public partial class _Default : System.Web.UI.Page

{

    private static int counter = 1;

    SqlConnection con;

    protected void Page_Load(object sender, EventArgs e)

    {

        con = new SqlConnection(ConfigurationManager.ConnectionStrings["CONN"].ConnectionString.ToString());

        

        // Collection to hold X Axis and Y Axis Values

        Dictionary<string,Decimal> xyValue = new Dictionary<string, Decimal>();

        // Call to chart Data method which return dictionary collection of demo data

        xyValue = chartData();

        // Binding collection key value pair to chart's default series

        Chart1.Series[0].Points.DataBindXY(xyValue.Keys, xyValue.Values);

    }

    protected Dictionary<string, Decimal> chartData()

    {

        // Object to generate random numbers to populate demo data

        //Random rnd = new Random(1);

        DataTable dtsale = FetchSale();     

        Dictionary<string, Decimal> values = new Dictionary<string, Decimal>();

        //Populating collection with random values

        for (int i = 0; i < dtsale.Rows.Count; i++)

        {

            values.Add(dtsale.Rows[i][0].ToString(),Convert.ToDecimal(dtsale.Rows[i][1].ToString()));

        }

        return values;

    }

    public DataTable FetchSale()

    {

        SqlDataAdapter da = new SqlDataAdapter("Select * from SALE", con);

        DataTable dt = new DataTable();

        da.Fill(dt);

        return dt;

    }

    protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)

    {

        if (!DropDownList1.SelectedValue.Equals("Select"))

        {

            Dictionary<string, Decimal> xyValue = new Dictionary<string, Decimal>();

            xyValue = chartData();

            

            // Creating new series with counter

            // so name will be unique when we add this series to chart series collection

            Series newSeries = new Series("newSeries" + counter);

            counter++;

            

            // Here we are using Enum.Parse to parse string from dropdown to     

            // SeriesChartType enumeration type

            newSeries.ChartType = (SeriesChartType)Enum.Parse(typeof(SeriesChartType), DropDownList1.SelectedValue.ToString());

            newSeries.Points.DataBindXY(xyValue.Keys, xyValue.Values);

            // Assigning chart area of new series to same as chart area of default series

            newSeries.ChartArea = Chart1.Series[0].ChartArea;

            // Adding chart to chart1's series collection

            Chart1.Series.Add(newSeries);

        }

    }

}

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