本文实例讲述了php计算给定时间之前的函数用法。分享给大家供大家参考。具体如下：

这里给定一个时间，计算这个时间在多久前，比如：2天前，1年前

<?php function prettyDate($date){ $time = strtotime($date); $now = time(); $ago = $now - $time; if($ago < 60){ $when = round($ago); $s = ($when == 1)"seconds"; return "$when $s ago"; }elseif($ago < 3600){ $when = round($ago / 60); $m = ($when == 1)"minutes"; return "$when $m ago"; }elseif($ago >= 3600 && $ago < 86400){ $when = round($ago / 60 / 60); $h = ($when == 1)"; return "$when $h ago"; }elseif($ago >= 86400 && $ago < 2629743.83){ $when = round($ago / 60 / 60 / 24); $d = ($when == 1)"; return "$when $d ago"; }elseif($ago >= 2629743.83 && $ago < 31556926){ $when = round($ago / 60 / 60 / 24 / 30.4375); $m = ($when == 1)"; return "$when $m ago"; }else{ $when = round($ago / 60 / 60 / 24 / 365); $y = ($when == 1)"; return "$when $y ago"; } } echo prettyDate("2012-07-22 12:23:45")."<br />"; echo prettyDate("2010-11-12 22:25:45")."<br />"; echo prettyDate("2012-01-01 01:00:00")."<br />"; echo prettyDate("2001-05-30 00:00:00")."<br />";

希望本文所述对大家的php程序设计有所帮助。