I am programming Excel in a DSP Framer using C#. Since C# is a more strongly
typed language than VB, it is hard for me to translate some of the VB that
I've seen.

UsedRange.Columns
How would I parse through each column. I do not see and Excel.Column object.
What does range.Columns return? Is it a collection (of what).

I want to resize the used range, the only part of the worksheet that is
visible to be the size of the frame, as in Excel.Application.Width -
this.frame.width.
It would let me set the width property, and the ColumnWidth proprty is not
expressed in pixels. It seems simple enough, but how is it done?

The ChangeEvent returns a range with dollar signes, like $A$1. What do the
dollar signs mean? How do I use them?

I don't see a re-size event for Excel? When I re-size the frame control, I
need to re-size Excel.