PHP: cal_days_in_month() function

Last update on May 28 2022 12:29:21 (UTC/GMT +8 hours)

Description

The cal_days_in_month() function is used to get the number of days of a month for a given year and calendar.

Version:

(PHP 4 and above)

Syntax:

cal_days_in_month (calendar, month, year )

Parameters:

Name	Description	Required / Optional	Type
calendar	Calendar to use for calculation.	Required	Integer
month	Month in the selected calendar.	Required	Integer
year	Year in the selected calendar.	Required	Integer

Return value:

The length in days of the selected month in the specified calendar.

Value Type: Integer.

Example:

<?php
$day_count=cal_days_in_month(CAL_GREGORIAN,02,2020);
echo  ' No of days in February 2020 : ' .$day_count;
?>

Sample Output:

No. of days in February 2020 : 29

View the example in the browser

See also

PHP Function Reference

Previous: usort
Next: cal_from_jd

PHP: Tips of the Day

How to Sort Multi-dimensional Array by Value?

Try a usort, If you are still on PHP 5.2 or earlier, you'll have to define a sorting function first:

Example:

function sortByOrder($a, $b) {
    return $a['order'] - $b['order'];
}

usort($myArray, 'sortByOrder');

Starting in PHP 5.3, you can use an anonymous function:

usort($myArray, function($a, $b) {
    return $a['order'] - $b['order'];
});

And finally with PHP 7 you can use the spaceship operator:

usort($myArray, function($a, $b) {
    return $a['order'] <=> $b['order'];
});

To extend this to multi-dimensional sorting, reference the second/third sorting elements if the first is zero - best explained below. You can also use this for sorting on sub-elements.

usort($myArray, function($a, $b) {
    $retval = $a['order'] <=> $b['order'];
    if ($retval == 0) {
        $retval = $a['suborder'] <=> $b['suborder'];
        if ($retval == 0) {
            $retval = $a['details']['subsuborder'] <=> $b['details']['subsuborder'];
        }
    }
    return $retval;
});

If you need to retain key associations, use uasort() - see comparison of array sorting functions in the manual

Ref : https://bit.ly/3i77vCC