php论坛中常用的两个时间差(多少分钟前,多少小时前,多少天前)

<?php
@ini_set('date.timezone', 'Asia/Shanghai');
@ini_set('display_errors', 1);
header('Content-Type:text/html;charset=utf-8');
class Time
{
public static function times($btime)
{
$result = '';
$time =time() - $btime ;
if($time < 60)
{
$result = $time.'秒前';
}
else if($time < 1800)
{
$result = floor($time/60).'分钟前';
}
else if($time < 3600)
{
$result = '半小时前';
}
else if($time < 86400)
{
$result = floor($time/3600).'小时前';
}
else
{
$zt = strtotime(date('Y-m-d 00:00:00'));
$qt = strtotime(date('Y-m-d 00:00:00',strtotime("-1 day")));
$st = strtotime(date('Y-m-d 00:00:00',strtotime("-2 day")));
$bt = strtotime(date('Y-m-d 00:00:00',strtotime("-7 day")));
if( $btime < $bt)
{
$result = date('Y-m-d H:i:s', $btime);
}
else if($btime < $st)
{
$result = floor($time/86400).'天前';
}
else if($btime < $qt)
{
$result = "前天".date('H:i', $btime);
}
else
{
$result = '昨天'.date('H:i', $btime);
}
}
return $result;
}
}
//测试
$str='2013-09-25 00:13:05';
echo Time::times(strtotime($str));