[1Unreal]

I want to add a new BB Code and handle it with PHP

Ive been looking through the BB Code include file and I really dont understand how its working

Heres what I want to do:

Take a string of links, each link on one line. Then convert that into an array:

PHP Code:

$string = '[mybbcode]
http://www.site1.com/
http://www.site2.com/
http://www.site3.com/
[/mybbcode]

$string = explode("\n", $string);

foreach($string as $link){
     echo '<a href="'. $link . '">'.$link.'</a>';
} 


Thats essentially what I want to do, amongst other things.

But Im reallly lost.