software

I'm not sure if this can be done in excel, but it never hurts to ask...

I needed a text file of my directory structure, and the only way I
could get it to look the way I wanted it was to use a program that
exported it to an excel file. Now I'm wondering if it's possible to
make it even more stream line by using a drop down function of some
sort. The way it looks now is:

Col A: Col B: Col C
Folder
Sub Folder
Sub-Sub-Folder
Folder
Folder

etc., etc, where there are empty cells whenever we move down a
sub-folder. Is there a way in Excel to make the deepest sets of
subfolders become a drop down list in its parent folder, all the way up
to the top parent directories?

Thank you!

T