php时间戳怎么转天数

public function edit()
{
global $_W;
global $_GPC;
$openid=$_W['openid'];
$boards = pdo_fetchall('select b.id,b.logo,b.title,f.createtime from ' . tablename('ewei_shop_sns_board_follow') . ' f ' . ' left join ' . tablename('ewei_shop_sns_board') . ' b on f.bid = b.id ' . ' where f.uniacid=:uniacid and f.openid=:openid ', array(':uniacid' => $_W['uniacid'], ':openid' => $openid));
$boards = set_medias($boards, 'logo');
include $this->template();
}
 
 
//html 代码  
<div class="mtvc mm">
{loop $boards $k $v}
<div>
<img class="mui-media-object mui-pull-left" src="{$v['logo']}">
<div class="mui-media-body">
{$v['title']}
<p class='mui-ellipsis'>已坚持<span>
<?php
$times= (time()-$v['createtime'])/86400;
// echo $times."<br>";
if( $times<1){
echo "1";
}else{
echo round("$times");
}
?>
</span>天</p>
<img class="mui-media-object mui-pull-right imgdel" src="../addons/ewei_shopv2/plugin/sns/static/images/btndel.png" onClick="delItem(this, id)"/></br>
</div>
</div>
{/loop}
</div>

{$v['title']} =<?php  echo $v['title'];  ?>

<?php
echo(round(0.60));
echo(round(0.50));
echo(round(0.49));
echo(round(-4.40));
echo(round(-4.60));
?>

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