PHP strtotime +1 month adding an extra month [dupl

问题:

This question already has an answer here:

• PHP: Adding months to a date, while not exceeding the last day of the month 4 answers

I have a simple variable that adds one month to today:

$endOfCycle = date("Y-m", strtotime("+1 month"));

Today is January 2013, so I would expect to get back 2013-02 but I'm getting 2013-03 instead. I can't figure out why it's jumping to March.

回答1:

It's jumping to March because today is 29th Jan, and adding a month gives 29th Feb, which doesn't exist, so it's moving to the next valid date.

This will happen on the 31st of a lot of months as well, but is obviously more noticable in the case of January to Feburary because Feb is shorter.

If you're not interested in the day of month and just want it to give the next month, you should specify the input date as the first of the current month. This will always give you the correct answer if you add a month.

For the same reason, if you want to always get the last day of the next month, you should start by calculating the first of the month after the one you want, and subtracting a day.

回答2:

This should be

$endOfCycle=date('Y-m-d', strtotime("+30 days"));

strtotime

expects to be given a string containing a US English date format and will try to parse that format into a Unix timestamp (the number of seconds since January 1 1970 00:00:00 UTC), relative to the timestamp given in now, or the current time if now is not supplied.

while

date

Returns a string formatted according to the given format string using the given integer timestamp or the current time if no timestamp is given.

See the manual pages for:

• http://www.php.net/manual/en/function.strtotime.php
• http://www.php.net/manual/en/function.date.php

回答3:

You can use this code to get the next month:

$ts = mktime(0, 0, 0, date("n") + 1, 1);
echo date("Y-m-d H:i:s", $ts);
echo date("n", $ts);

Assuming today is 2013-01-31 01:23:45 the above will return:

2013-02-01 00:00:00
2

回答4:

today is 29th of January, +1 month means 29th of Fabruary, but because February consists of 28 days this year, it overlaps to the next day which is March 1st

instead try

strtotime('next month')

回答5:

Maybe because its 2013-01-29 so +1 month would be 2013-02-29 which doesn't exist so it would be 2013-03-01

You could try

date('m/d/y h:i a',(strtotime('next month',strtotime(date('m/01/y')))));

from the comments on http://php.net/manual/en/function.strtotime.php

回答6:

 $endOfCycle = date("Y-m", mktime(0, 0, 0, date("m", time())+1 , 15, date("m", time())));

回答7:

try this:

$endOfCycle = date("Y-m", time()+2592000);

this adds 30 days, not exactly a month tough.