获取当前时间:
Carbon::now()->toDateTimeString();//2019-11-18 17:20:49
获取某个时间的月末
$time = '2019-11';
Carbon::parse($time)->addMonth(1)->addSecond(-1)->toDateTimeString();//2019-11-30 23:59:59
$time = '2020-1-13'
Carbon::parse($time)->addSecond(5)->timestamp //将时间转为时间戳