Please refer this article

Create ASP.Net Chart Control from Database using C# and VB.Net Example

HTML

<form id="form1" runat="server">
<asp:DropDownList ID="ddlCountries" runat="server" OnSelectedIndexChanged="ddlCountries_SelectedIndexChanged"
    AutoPostBack="true">
</asp:DropDownList>
<asp:DropDownList ID="ddlColors" runat="server" OnSelectedIndexChanged="ddlCountries_SelectedIndexChanged"
    AutoPostBack="true">
    <asp:ListItem Text="Red" Value="Red" />
    <asp:ListItem Text="Blue" Value="Blue" />
    <asp:ListItem Text="Green" Value="Green" />
</asp:DropDownList>
<hr />
<asp:Chart ID="Chart1" runat="server" Height="300px" Width="400px" Visible="false">
    <Titles>
        <asp:Title ShadowOffset="3" Name="Items" />
    </Titles>
    <Legends>
        <asp:Legend Alignment="Center" Docking="Bottom" IsTextAutoFit="False" Name="Default"
            LegendStyle="Row" />
    </Legends>
    <Series>
        <asp:Series Name="Default" />
    </Series>
    <ChartAreas>
        <asp:ChartArea Name="ChartArea1" BorderWidth="0" />
    </ChartAreas>
</asp:Chart>
</form>

Namespaces

using System.Data;
using System.Data.SqlClient;
using System.Configuration;
using System.Drawing;

C#

protected void Page_Load(object sender, EventArgs e)
{
    if (!IsPostBack)
    {
        string query = "select distinct shipcountry from orders";
        DataTable dt = GetData(query);
        ddlCountries.DataSource = dt;
        ddlCountries.DataTextField = "shipcountry";
        ddlCountries.DataValueField = "shipcountry";
        ddlCountries.DataBind();
        ddlCountries.Items.Insert(0, new ListItem("Select", ""));
    }
}

protected void ddlCountries_SelectedIndexChanged(object sender, EventArgs e)
{
    Chart1.Visible = ddlCountries.SelectedValue != "";
    string query = string.Format("select shipcity, count(orderid) from orders where shipcountry = '{0}' group by shipcity", ddlCountries.SelectedValue);
    DataTable dt = GetData(query);
    string[] x = new string[dt.Rows.Count];
    int[] y = new int[dt.Rows.Count];
    for (int i = 0; i < dt.Rows.Count; i++)
    {
        x[i] = dt.Rows[i][0].ToString();
        y[i] = Convert.ToInt32(dt.Rows[i][1]);
    }
    Chart1.Series[0].Points.DataBindXY(x, y);
    Chart1.Series[0].ChartType = SeriesChartType.StackedBar;
    Chart1.ChartAreas["ChartArea1"].Area3DStyle.Enable3D = false;
    Chart1.Legends[0].Enabled = true;
    if (this.ddlColors.SelectedItem.Value != "")
    {
        switch (ddlColors.SelectedItem.Value)
        {
            case "Red":
                Chart1.Series[0].Color = Color.Red;
                break;
            case "Blue":
                Chart1.Series[0].Color = Color.Blue;
                break;
            case "Green":
                Chart1.Series[0].Color = Color.Green;
                break;
        }
    }

}

private static DataTable GetData(string query)
{
    String constr = ConfigurationManager.ConnectionStrings["ConString"].ConnectionString;
    DataTable dt = new DataTable();
    using (SqlConnection con = new SqlConnection(constr))
    {
        using (SqlCommand cmd = new SqlCommand(query))
        {
            using (SqlDataAdapter sda = new SqlDataAdapter())
            {
                cmd.CommandType = CommandType.Text;
                cmd.Connection = con;
                sda.SelectCommand = cmd;
                sda.Fill(dt);
                return dt;
            }
        }
    }
}

Screenshot