- var_dump: documentation ( source)
- array_fill: documentation ( source)
- preg_replace: documentation ( source)
<?php
$params = array('a', 'b', 'c');
$patterns = array_fill(0, count($params), '#\?#');
$replacements = $params;
var_dump(preg_replace($patterns, $replacements, 'bla ? bla ? bla ? blu'));