I will try it out tonight when I go home...
Thanks for all the helps!
--------------- Added [DATE]1311664092[/DATE] at [TIME]1311664092[/TIME] ---------------
you're the man!!!! It's work beautifully.
one more question, what are the "TYPE" options do we have?
for example, if someone enter 99.99 and 30, the discount should be 33.33%
should I use "double" instead of integer?
thanks
update: i figured it out. Thanks