c# – ASP.Net MS图表控制饼图：删除不需要的填充

我试图使用MS Chart控件创建简单的饼图.当我的饼图在浏览器中渲染时,我可以在饼图上填充我不能摆脱的饼图.我想要饼图坐在图像的边缘,没有填充或边距.关于我如何实现这一点的任何想法？

在我的下面的代码中,填充用蓝色突出显示.即Chart1.BackColor = System.Drawing.Color.Blue;

<script type="text/C#" runat="server">
        protected void Page_Load(object sender,EventArgs e)
        {
            //Set the chart type
            Chart1.Series["Series1"].ChartType = SeriesChartType.Pie;

            //add points
            Chart1.Series["Series1"].Points.AddY(12);
            Chart1.Series["Series1"].Points.AddY(45);
            Chart1.Series["Series1"].Points.AddY(67);

            //set back color of chart object
            Chart1.BackColor = System.Drawing.Color.Blue;

            //set back color of chart area
            Chart1.ChartAreas["ChartArea1"].BackColor = System.Drawing.Color.Green;

        }
    </script>

    <asp:Chart ID="Chart1" runat="server">
        <Series>
            <asp:Series Name="Series1" ChartType="Pie">
            </asp:Series>
        </Series>
        <ChartAreas>
            <asp:ChartArea Name="ChartArea1">
            </asp:ChartArea>
        </ChartAreas>
    </asp:Chart>