php 如何使用 Carbon 获取上个月的第一天和最后一天 - Laravel
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How to get First and Last Day of Previous Month with Carbon - Laravel
提问by Siddharth
I need Firstand Last Dayof Previous Monthusing Carbon Library, what I have tried is as follows:
我需要首先和最后一天的前一个月使用的碳库，我曾尝试如下：
$firstDayofPreviousMonth = Carbon::now()->startOfMonth()->subMonth()->toDateString();
$lastDayofPreviousMonth = Carbon::now()->endOfMonth()->subMonth()->toDateString();
Result I'm getting is for$firstDayofPreviousMonth = '2016-04-01'(as current month is 5th(May)) and for $lastDayofPreviousMonth = '2016-05-01'.
我得到的结果是$firstDayofPreviousMonth = '2016-04-01'（因为当月是 5 日（5 月））和$lastDayofPreviousMonth = '2016-05-01'.
I'm getting correct result for $firstDayofPreviousMonth, but it's giving me 30 days previous result, and giving me wrong result for $lastDayofPreviousMonth.
我得到了正确的结果$firstDayofPreviousMonth，但它给了我 30 天前的结果，并给了我错误的结果$lastDayofPreviousMonth。
Can anyone help me out with this?
谁能帮我解决这个问题？
回答by Deniz B.
Try this:
尝试这个：
$start = new Carbon('first day of last month');
$end = new Carbon('last day of last month');
回答by Abu Sayem
Just try this
试试这个
$firstDayofPreviousMonth = Carbon::now()->startOfMonth()->subMonth()->toDateString();
$lastDayofPreviousMonth = Carbon::now()->subMonth()->endOfMonth()->toDateString();
$firstDayofPreviousMonth = Carbon::now()->startOfMonth()->subMonth()->toDateString();
$lastDayofPreviousMonth = Carbon::now()->subMonth()->endOfMonth()->toDateString();
回答by sadalsuud
With this ... the date start init on 00:00 and date end finish in 23:59
有了这个......日期开始于 00:00，日期结束于 23:59
$start = new Carbon('first day of last month');
$start->startOfMonth();
$end = new Carbon('last day of last month');
$end->endOfMonth();
回答by Tama
To specifically answer your question as to why you're getting the wrong result for $lastDayofPreviousMonth.
专门回答你的问题，为什么你得到了错误的结果$lastDayofPreviousMonth。
Lets break down this statement in your example:
让我们在您的示例中分解此语句：
Carbon::now()->endOfMonth()->subMonth()->toDateString();
// Carbon::now() > 2016-05-05
// ->endOfMonth() > 2016-05-31
// ->subMonth() > 2016-04-31 // Simply takes 1 away from 5.
This leaves us with an invalid date — there is no 31st of April. The extra day is simply added on to the last valid date (2016-04-30 + 1) which rolls the date into May (2016-05-01).
这给我们留下了一个无效的日期——没有 4 月 31 日。额外的一天只是添加到最后一个有效日期 (2016-04-30 + 1) 上，该日期将日期滚动到五月 (2016-05-01)。
As previously mentioned to be sure this never happens always reset the date to the 1st of the month before doing anything else (as every month has a 1st day).
如前所述，为了确保这永远不会发生，在做任何其他事情之前总是将日期重置为一个月的第一天（因为每个月都有第一天）。
$lastDayofPreviousMonth = Carbon::now()->startofMonth()->subMonth()->endOfMonth()->toDateString();
// Carbon::now() > 2016-05-05
// ->startofMonth() > 2016-05-01 00:00:00
// ->subMonth() > 2016-04-01 00:00:00
// ->endOfMonth() > 2016-04-30 23:59:59
回答by FuzzyJared
There is currently a bug within Carbon when using the method
使用该方法时，Carbon 中目前存在一个错误
Carbon::now()->startOfMonth()->subMonth()->endOfMonth()->toDateTimeString();
The bug results in returning the last day as 30 for those months that have 31 days.
该错误导致那些有 31 天的月份的最后一天返回 30。
IE - if you are in March and you run the above call it will return 2017-03-30 and not 2017-03-31 as you would expect.
IE - 如果您在 3 月份并且运行上述调用，它将返回 2017-03-30 而不是 2017-03-31，正如您所期望的。
As I was doing a between dates operation I ended up using..
当我在做一个日期之间的操作时，我最终使用了..
Carbon::now()->startOfMonth()->subSeconds(1)->toDateTimeString();
This ended up with the correct date dateTimeString for those days that end on the 31st.
这最终得到了在 31 日结束的那些日子的正确日期 dateTimeString。
回答by elena
Another solution is using Carbon method subMonthNoOverflow():
另一种解决方案是使用 Carbon 方法subMonthNoOverflow()：
$lastDayofPreviousMonth = Carbon::now()->subMonthNoOverflow()->endOfMonth()->toDateString();
Found it here when run into 31 day of month issue: https://github.com/briannesbitt/Carbon/issues/627
在遇到每月 31 天的问题时在这里找到它：https: //github.com/briannesbitt/Carbon/issues/627
