正则表达式错了吗？ [关闭]

Question

What I did wrong? It still returns 21-11-2016.

$string = '21-11-2016';
$pattern = '/({0-9}(2))-({0-9}(2))-({0-9}(4))/';
$rep = "Month: $2 , Day: $1 , Year: $3";
echo preg_replace($pattern, $rep, $string); 
die();

Answer 1

You have {..} and (..) at wrong place. Use:

echo preg_replace('/([0-9]{2})-([0-9]{2})-([0-9]{4})/', $rep, $string);

{...} makes it a range and [...] makes it a character class.