clearing the shopping card

[Kyle Hayes <kyle540@quicknet.net>]

I need to change the canceled.html page.  This is the page that allows
users to expunge all order information or all information at all.  We
automatically purge info if an order doesn't complete.  What I want to do
is allow a user to hit a button to return to shopping.  Currently, there
are two buttons on the page.  (This is from the simple demo.)  One button
removes all order information and returns the user to the catalog page.
The other button removed all information ever known about the user.  I
need the sales partner ID at all times, so I need to remove this option.
All my pages are branded based on the sales partner ID.

How can I get rid of all items in the cart optionally?

Currently the page has 

[item-list]
<input type=hidden name='[quantity-name]' value=0>
[/item-list]

This removes the items from the card.  Great.  But, that particular bit of
script runs no matter which button is hit.  Is there some trick I can do
with a [set] block?

How do I make the above code only execute if the user hits the "Remove
Contents Only" button?  

Best,
Kyle