Hi,
If you mean the appearance of the series in the chart, use this in codebehind:
Chart1.Series[
"Series1"].ChartType = ...
or in the aspx or ascx:
<
asp:Series Name="Series1" ChartType="StackedArea100" BorderColor="180, 26, 59, 105" Color="220, 65, 140, 240"></asp:Series>
Keep in mind that the appearance is set at the series, not at the chat or chartarea, this gives you the possibility to mix different appearances in one chart.
Good luck,
Mark