使用PHP向日期添加天数

Question

I am trying to add a certain amount of days to a set date in PHP. However, all of the code I use is not working. Here is the code I am currently experiencing problems with:

echo date("2013-12-01", strtotime("+7 days"));

I wanting to add 7 days to the date above. When I echo out this code, it just prints '2013-12-01'. Is there a way to do this?

Thanks

Answer 1

For the sake of completeness, here's how you do it with DateTime():

$datetime = new DateTime("2013-12-01");
$datetime->add(new DateInterval('P7D'));
echo $datetime->format('Y-m-d');

or

$datetime = new DateTime("2013-12-01");
$datetime->modify('+7 days');
echo $datetime->format('Y-m-d');