PHP5.3x ereg_replace改成preg_replace？

Question

PHP5.3x ereg_replace改成preg_replace

Answer 1

$GLOBALS['index'] = 0;
$search = "abcabcabcabc";
$replace = preg_replace_callback("/a/", function($matches){
return $GLOBALS['index']++ % 2 ? '*' : $matches[0];
}, $search );
var_dump($replace);