Use the SeriesLines property to display and modify the series lines that connect data series in the stacked bar and column charts, as shown in the image below (the chart is displayed in Microsoft® Excel®).
By default, the Pie of Pie and Bar of Pie charts display the series lines to connect the main and secondary charts, so you can use the SeriesLines property to hide these lines or adjust their appearance, for example, to change the line color or width.
If you try to display series lines on a chart that does not support them, an exception occurs.
Currently, the SpeadsheetControl does not display series lines on a chart. However, display settings are loaded and stored in supported formats, and you can modify them programmatically.