例子：
<?php $nextWeek = time() + (7 * 24 * 60 * 60); // 7 days; 24 hours; 60 mins; 60secs echo ‘Now: ‘. date(‘Y-m-d‘) ."\n"; echo ‘Next Week: ‘. date(‘Y-m-d‘, $nextWeek) ."\n"; ?>
输出：
<pre>Now: 2005-03-30
Next Week: 2005-04-07</pre>
原文：http://www.cnblogs.com/lvchenfeng/p/5150897.html