How get number of days in a month in php?

(PHP 4 >= 4.1.0, PHP 5, PHP 7, PHP 8)

cal_days_in_month — Return the number of days in a month for a given year and calendar

Description

cal_days_in_month(int $calendar, int $month, int $year): int

Parameters

Calendar to use for calculation

Month in the selected calendar

Year in the selected calendar

Return Values

The length in days of the selected month in the given calendar

Examples

Example #1 cal_days_in_month() example

<?php
$number = cal_days_in_month(CAL_GREGORIAN, 8, 2003); // 31
echo "There were {$number} days in August 2003";
?>

brian at b5media dot com ¶

14 years ago

Remember if you just want the days in the current month, use the date function:
$days = date("t");

dbindel at austin dot rr dot com ¶

18 years ago

Here's a one-line function I just wrote to find the numbers of days in a month that doesn't depend on any other functions.

The reason I made this is because I just found out I forgot to compile PHP with support for calendars, and a class I'm writing for my website's open source section was broken. So rather than recompiling PHP (which I will get around to tomorrow I guess), I just wrote this function which should work just as well, and will always work without the requirement of PHP's calendar extension or any other PHP functions for that matter.

I learned the days of the month using the old knuckle & inbetween knuckle method, so that should explain the mod 7 part. :)

<?php
/*
* days_in_month($month, $year)
* Returns the number of days in a given month and year, taking into account leap years.
*
* $month: numeric month (integers 1-12)
* $year: numeric year (any integer)
*
* Prec: $month is an integer between 1 and 12, inclusive, and $year is an integer.
* Post: none
*/
// corrected by ben at sparkyb dot net
function days_in_month($month, $year)
{
// calculate number of days in a month
return $month == 2 ? ($year % 4 ? 28 : ($year % 100 ? 29 : ($year % 400 ? 28 : 29))) : (($month - 1) % 7 % 2 ? 30 : 31);
}
?>

Enjoy,
David Bindel

datlx at yahoo dot com ¶

15 days ago

function lastDayOfMonth(string $time, int $deltaMonth, string $format = 'Y-m-d')
{
    try {
        $year = date('Y', strtotime($time));
        $month = date('m', strtotime($time));

        $increaYear = floor(($deltaMonth + $month - 1) / 12);

        $year += $increaYear;
        $month = (($deltaMonth + $month) % 12) ?: 12;
        $day = cal_days_in_month(CAL_GREGORIAN, $month, $year);

        return $time . ' + ' . $deltaMonth . ' => ' . date($format, strtotime($year . '-' . $month . '-' . $day)) . "\n";
    } catch (Exception $e) {
        throw $e;
    }
}

jeffbeall at comcast dot net ¶

18 years ago

This will work great in future dates but will give the wrong answer for dates before 1550 (approx) when leap year was introduced and the calendar lost a year or two.
Sorry now to be more specific it has been a while sine I had to account for those later dates and had to take that into account but just a heads up for others to watch out.

geko45pj at yahoo dot com ¶

15 years ago

<?php
# PHP Calendar (version 2.3), written by Keith Devensfunction generate_calendar($year, $month, $days = array(), $day_name_length = 3, $month_href = NULL, $first_day = 0, $pn = array()){
    $first_of_month = gmmktime(0,0,0,$month,1,$year);#remember that mktime will automatically correct if invalid dates are entered
    # for instance, mktime(0,0,0,12,32,1997) will be the date for Jan 1, 1998
    # this provides a built in "rounding" feature to generate_calendar()$day_names = array(); #generate all the day names according to the current locale
    for($n=0,$t=(3+$first_day)*86400; $n<7; $n++,$t+=86400) #January 4, 1970 was a Sunday
        $day_names[$n] = ucfirst(gmstrftime('%A',$t)); #%A means full textual day namelist($month, $year, $month_name, $weekday) = explode(',',gmstrftime('%m,%Y,%B,%w',$first_of_month));
    $weekday = ($weekday + 7 - $first_day) % 7; #adjust for $first_day
    $title   = htmlentities(ucfirst($month_name)).'&nbsp;'.$year;  #note that some locales don't capitalize month and day names

    #Begin calendar. Uses a real <caption>. See http://diveintomark.org/archives/2002/07/03