displaying code with different colors

Hi i was wondering how i would og about making a script that would change the colours for code like this site when you put something inside of the php tags

example


echo "hello world";



does anyone know where i might be able to get a function from for this process

http://us3.php.net/manual/en/function.highlight-file.php
http://us3.php.net/manual/en/function.highlight-string.php

yeah thanks that does wot i want