How to build Acronyms of a phrase in PHP

Something like:

$s = 'Stack-Overflow Questions Tags Users';

if(preg_match_all('/\b(\w)/',strtoupper($s),$m)) {
    $v = implode('',$m[1]); // $v is now SOQTU
}

I'm using the regex \b(\w) to match the word-char immediately following the word boundary.

EDIT: To ensure all your Acronym char are uppercase, you can use strtoupper as shown.

$s = 'Stack-Overflow Questions Tags Users';
echo preg_replace('/\b(\w)|./', '$1', $s);

the same as codaddict's but shorter

• For unicode support, add the u modifier to regex: preg_replace('...../u',