Programming Outlines (expand/collapse rows) in Excel
 

I have an application using Sharepoint Web Parts and C# that gets some
information from a database, formats it, sends it to IE in html, and
then Excel opens up with the formatted information.

I now want to add outline functionality to it. There are plenty of
sites that tell you how to do it manually, like this one,
http://office.microsoft.com/en-us/sh...054661033.aspx,
but I want to be able to program it in.

Anyone know how to go about it?