PHP获取每月第一天与最后一天

<?php

function getthemonth($date)

{

$firstday = date('Y-m-01', strtotime($date));

$lastday = date('Y-m-d', strtotime("$firstday +1 month -1 day"));

return array($firstday,$lastday);

}

$today = "2012-02-05";

$day=getthemonth($today);

print_r($day);

?>