About 301 Redirect

[FatalBreeze]

Hello!
I'm considering to buy a new domain name for my website, the existing domain is atraf-f.net and i want to buy atraf-f.com (for example).
But in still want the keep the old domain, so that when someone enters atraf-f.net/forumdisplay.php?f=15 he will be redirected to atraf-f.com/forumdisplay.php?f=15.

I've built a tiny code, and i want to know whether it would work or not, can you tell me please?

PHP Code:

if(stristr($_SERVER['SERVER_NAME'],"net")) {
   $dir = $_SERVER['SERVER_NAME'].$_SERVER['REQUEST_URI'];
   $dir = str_replace("net","com",$dir);
   $dir = "http://".$dir;
   header('HTTP/1.1 301 Moved Permanently');
   header("Location:$dir");
} 


the code will be placed in global_start.

Will it work? Thanks!

c'mon? surely someone must know this...