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.
![I’m an Impostor]()
This is the hardest thing I've ever had to write, much less admit to myself. I've written resignation letters from jobs I've loved, I've ended relationships, I've failed at a host of tasks, and let myself down in my life. All of those feelings were very...
![Designing for Simplicity]()
Before we get started, it's worth me spending a brief moment introducing myself to you. My name is Mark (or @integralist if Twitter happens to be your communication tool of choice) and I currently work for BBC News in London England as a principal engineer/tech...
![Create Twitter-Style Dropdowns Using jQuery]()
Twitter does some great stuff with JavaScript. What I really appreciate about what they do is that there aren't any epic JS functionalities -- they're all simple touches. One of those simple touches is the "Login" dropdown on their homepage. I've taken...
![Create a Simple Slideshow Using MooTools, Part II: Controls and Events]()
Last week we created a very simple MooTools slideshow script. The script was very primitive: no events and no next/previous controls -- just cross-fading between images. This tutorial will take the previous slideshow script a step further by:
Adding "Next" and "Previous" controls.
Adding...
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 :)