Poison Null Protection

Ok well I know it sounds like a noobish and simple question, but I'm looking for a simple way to prevent null byte injections in PHP.

I have looked around a little but I keep finding ways to exploit it rather than fix it.

Sry not to give you help directly, but I don't know php very well… Anyway I googled string "prevent php null byte injections" without quotes and it returned some interesting I'd useful documents

http://www.hackits.de/forum/thread.php?threadid=2052&sid=c0f877cb07d1426fed17d45f341ef29f

The author used a switch case statement that uses pages that are already there as cases and if the user tries to input a page that is not there already, then it goes to the index.php as a default.

a switch is deffinatly the way to go about it.

it's a long winded way of doing things, but by far the most secure.

example:

switch($_GET['page']){

case 'home':
  include "home.php";
break;

case 'contact':
 include "contact.php";
break;

default:
 include "home.php";

}```