数据库日期转换为时间戳

$data=O::select('created_at','total')
->get()->toArray();

//将数据库中的订单创建时间转换为时间戳
foreach($data as $v){
if(!empty($v)) {
preg_match_all('/\d/', $v, $sh_arr);   //$v是字符串
$timerlist = implode('', $sh_arr[0]);
$timerlist = strtotime($timerlist);
}
$hours[] = $timerlist ;
}
//  dd($hours);