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)));
}
![Regular Expressions for the Rest of Us]()
Sooner or later you'll run across a regular expression. With their cryptic syntax, confusing documentation and massive learning curve, most developers settle for copying and pasting them from StackOverflow and hoping they work. But what if you could decode regular expressions and harness their power? In...
![How I Stopped WordPress Comment Spam]()
I love almost every part of being a tech blogger: learning, preaching, bantering, researching. The one part about blogging that I absolutely loathe: dealing with SPAM comments. For the past two years, my blog has registered 8,000+ SPAM comments per day. PER DAY. Bloating my database...
![CSS Filters]()
CSS filter support recently landed within WebKit nightlies. CSS filters provide a method for modifying the rendering of a basic DOM element, image, or video. CSS filters allow for blurring, warping, and modifying the color intensity of elements. Let's have...
![Google-Style Element Fading Using MooTools or jQuery]()
Google recently introduced an interesting effect to their homepage: the top left and top right navigation items don't display until you move your mouse or leave the search term box. Why? I can only speculate that they want their homepage as...
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.