BarChart控件的使用

<asp:BarChart ID="BarChart1" runat="server" ChartHeight="300" ChartWidth="450" ChartType="Column"
                ChartTitle="United States versus European,England Widget Production"
                ChartTitleColor="#0E426C" CategoryAxisLineColor="#D08AD9"
                ValueAxisLineColor="#D08AD9" BaseLineColor="#A156AB" >
            <Series>
                 <asp:BarChartSeries Name="United States" BarColor="#6C1E83" />
                <asp:BarChartSeries Name="Europe" BarColor="#D08AD9"/>
                <asp:BarChartSeries Name="England" BarColor="Bule"/>
            </Series>
        </asp:BarChart>

  System.Data.DataTable dt = new System.Data.DataTable();
            dt.Columns.Add("Date");
            dt.Columns.Add("UnitedStates");
            dt.Columns.Add("Europe");
            dt.Columns.Add("England");
            dt.Rows.Add("2007", "20", "24", "56");
            dt.Rows.Add("2008", "47", "67", "39");
            dt.Rows.Add("2009", "55", "16", "78");
            string[] x = new string[dt.Rows.Count];
            decimal[] y1 = new decimal[dt.Rows.Count];
            decimal[] y2 = new decimal[dt.Rows.Count];
            decimal[] y3 = new decimal[dt.Rows.Count];
            for (int i = 0; i < dt.Rows.Count; i++)
            {

                x[i] = dt.Rows[i]["Date"].ToString();
                y1[i] = Convert.ToDecimal(dt.Rows[i]["UnitedStates"]);
                y2[i] = Convert.ToDecimal(dt.Rows[i]["Europe"]);
                y3[i] = Convert.ToDecimal(dt.Rows[i]["England"]);

            }
            BarChart1.CategoriesAxis = String.Join(",", x);
            BarChart1.Series[0].Data = y1;
            BarChart1.Series[1].Data = y2;
            BarChart1.Series[2].Data = y3;