PHP Function – Calculating Days In A Month
All developers keep a tool box of useful functions and classes that they pick up or write along the way and this PHP came to me while I was writing an event calendar page for a customer.
I should mention that PHP does offer a cal_days_in_month function for PHP builds of PHP 4.0.7 and higher, but I prefer using the below function because it is guaranteed to work on all PHP version because it is based solely on logic.
The Code
function get_days_in_month($month, $year)
{
return $month == 2 ? ($year % 4 ? 28 : ($year % 100 ? 29 : ($year %400 ? 28 : 29))) : (($month - 1) % 7 % 2 ? 30 : 31);
}
One line of logic provides the number of days in a month, taking into account leap years, and all on one line.
![Page Visibility API]()
One event that's always been lacking within the document is a signal for when the user is looking at a given tab, or another tab. When does the user switch off our site to look at something else? When do they come back?
![Detect DOM Node Insertions with JavaScript and CSS Animations]()
I work with an awesome cast of developers at Mozilla, and one of them in Daniel Buchner. Daniel's shared with me an awesome strategy for detecting when nodes have been injected into a parent node without using the deprecated DOM Events API.
![Elegant Overflow with CSS Ellipsis]()
Overflow with text is always a big issue, especially in a programmatic environment. There's always only so much space but variable content to add into that space. I was recently working on a table for displaying user information and noticed that longer strings were...
![Multiple File Upload Input]()
More often than not, I find myself wanting to upload more than one file at a time. Having to use multiple "file" INPUT elements is annoying, slow, and inefficient. And if I hate them, I can't imagine how annoyed my users would be. Luckily Safari, Chrome...
Thanks for your very helpful site! Love the tips.
Hi David,
PHP versions 4&5 also offer the
date("t")function which returns number of days in given month.michael is right:
$totDays = date("t",strtotime($year.'-'.$_month.'-01'));LOL.. Thanks Michael and Paskuale but I think you’re both missing the point! It’s nice to be told that we can get the days directly but the point about this function is that it’s an easily recognisable way to learn how ternary functions in PHP.
Very useful for noobies such as myself – thanks David :)
LOL.. Thanks Michael and Paskuale but I think you’re both missing the point! It’s nice to be told that we can get the days directly but the point about this function is that it’s an easily recognisable way to learn how ternary functions in PHP.
Very useful for noobies such as myself – thanks David :)