JavaScript need

i have a search box in my site.
i want my search box display some specific pages.

logic:
url = my site link.
if ( url srting contains "pcenhance") then
display search box
else
display anything. or search box don't show.

example1:
if url = http://hot.ezthemes.com/pcenhance/xb/main.phtml
then
show search box
example1:
if url = http://hot.ezthemes.com/ or http://hot.ezthemes.com/jokes/index.php
then
search box don't show.

please give me a javascript code...
hurry up