Folder Name Function

[frizzle]

Hi group!

I have a code to process text, to make it url/folder fiendly. (code
below)
The only problem i have, is that the
$foldername = ereg_replace("[^[:alnum:] ]","",$foldernam e);
part deletes all spaces, but as you can see, i want spaces to become
underscores,
which are no ALNUM-chars.
How can i solve this?

Greetings Frizzle.

///// C O D E /////

$foldername = stripslashes ( $_POST['foldername'] );
//This erase white-spaces on the beginning and the end:
$foldername = preg_replace('~ ^(\s*)(.*?)(\s* )$~m', "\\2", $foldername);
// replace all weird chars
$special_chars =
array('À','Á',' Â','Ã','Ä','Å', 'Ç','È','É','Ê' ,'Ë','Ì','Í','Î ','Ï','Ñ','Ò',' Ó','Ô','Õ','Ö', 'Ù','Ú','Û','Ü' ,'Ý','à','á','â ','ã','ä','å',' ç','è','é','ê', 'ë','ì','í','î' ,'ï','ñ','ò','ó ','ô','õ','ö',' ù','ú','û','ü', 'ý','ÿ','C','c' ,'C','c');
$special_replac ements =
array('A','A',' A','A','A','A', 'C','E','E','E' ,'E','I','I','I ','I','N','O',' O','O','O','O', 'U','U','U','U' ,'Y','a','a','a ','a','a','a',' c','e','e','e', 'e','i','i','i' ,'i','n','o','o ','o','o','o',' u','u','u','u', 'y','y','C','c' ,'C','c');
$foldername = str_replace($sp ecial_chars, $special_replac ements,
$foldername);
//erases all NON-alfanumerics
$foldername = ereg_replace("[^[:alnum:] ]","",$foldernam e);
// take out repetative spaces:
$foldername = preg_replace('/\s\s+/', ' ', $foldername);
$foldername = preg_replace('/\s/', '_', $foldername);
$foldername = strtolower($fol dername);
if ($foldername == ""){$folder name = "untitled"; }