抓住PHP上个月的最后一天[重复]

Question

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PHP last day of the month

In PHP, I am trying to get the last day of last month. For example, today is December 11 2012. So the date I am then trying to grab is November 30th.

This is what I am currently trying to do:

        //this grabs the last daye of this month
        $current_month = date('Y-m-t',strtotime('today'));

        //this should grab November 30th.
        $last_month = date("F, Y",strtotime($current_month." -1 month ")

Instead of it grabbing November 30th, it is grabbing December 1st. Is seems like "-1 month" simply subtracts 30 days.

How do I properly grab the last day of last month?

Answer 1

You can call mktime() with current month/year and 0 as day:

$last_day_of_last_month = mktime(0, 0, 0, date('n'), 0, date('Y'));

It's documented:

day [...] Values less than 1 (including negative values) reference the days in the previous month, so 0 is the last day of the previous month, -1 is the day before that, etc. Values greater than the number of days in the relevant month reference the appropriate day in the following month(s).