Get selected items from a Multi-Select Listbox without looping through all

[amypower]

Hi,
I have two html listboxes which have buttons(<< and >>) between them.
All works well except I want to allow multiple selections. The list of
items can get quite long, is there a way to get/store the selected
items *without* looping through each of the items and checking the
selected property?

I have yet to find a way to do this. Please tell me if it is not
possible.

Thanks,