Checking For Leap Year Using PHP
One part of programming that seems pretty static is dealing with dates. The calendar is a set system of rules that doesn't look to change. The only part of the calendar that can be variable is a leap year, which changes every four years (obviously).
Using pure PHP ternary logic, much like the PHP Function - Calculating Days In A Month, I posted a few weeks back, you can check to see if a year is a leap year.
The Code
function is_leap_year($year) {
return ((($year % 4) == 0) && ((($year % 100) != 0) || (($year % 400) == 0)));
}
![LightFace: Facebook Lightbox for MooTools]()
One of the web components I've always loved has been Facebook's modal dialog. This "lightbox" isn't like others: no dark overlay, no obnoxious animating to size, and it doesn't try to do "too much." With Facebook's dialog in mind, I've created LightFace: a Facebook lightbox...
![fetch API]()
One of the worst kept secrets about AJAX on the web is that the underlying API for it, XMLHttpRequest, wasn't really made for what we've been using it for. We've done well to create elegant APIs around XHR but we know we can do better. Our effort to...
![How to Create a Twitter Card]()
One of my favorite social APIs was the Open Graph API adopted by Facebook. Adding just a few META tags to each page allowed links to my article to be styled and presented the way I wanted them to, giving me a bit of control...
![afterscriptexecute Event]()
Placing a function call as an argument default will result in a fatal error. Also, give this version a shot:
function is_leap_year( $year = NULL ) { if_numeric( $year ) || $year = date( 'Y' ); return checkdate( 2, 29, ( int ) $year ); }Whoops, small typo… if_numeric( $year ) should be is_numeric( $year )… :x
Better yet, use
date('L')which returns1if it’s a leap year,0if it isn’t.I do agree with tamlyn, why you dont use date function??
It can makes a load fasting right?
date(‘L’) is way better because leap year is not every 4 years.
Date("L")only tell you in a given year, default is the year today.If you need to know whether previous or next year is a leap, you must reset the date.
It could affect the system.
Indra, you can always pass the timestamp as second parameter to date function:
echo date('L', mktime(1, 1, 1, 1, 1, 2005));I think this is a better example relating to the function. Also provided example for anyone looking for true/false as I was in this instance.
/* for true or false */ function is_leap_year($year) { return ( date ('L', mktime(1,1,1,1,1, $year) ) === 1 ) ? true : false; } /*for 0 or 1 Whether it's a leap year: 1 if it is a leap year, 0 otherwise. */ function is_leap_year($year) { return date ('L', mktime(1,1,1,1,1, $year) ); }<?php $day = ""; for($i=0; $i<4; $i++) { $day = date("d", mktime(0, 0, 0, 2, 29, date("Y")+$i)); if($day == 29) { $year = date("Y")+$i; break; } } echo "The next leap year is 29th February $year"; ?>code of Habibur Rahaman will not work for example for the year 1897, because 1900 is not leap year.