<?php
/**
* Calculating the difference between two dates
* @author: Elliott White
* @author: Jonathan D Eisenhamer.
* @link: http://www.quepublishing.com/articles/article.asp?p=664657&rl=1
* @since: Dec 1, 2006.
*/
if( function_exists( 'date_default_timezone_set' ) )
{
// Set the default timezone to US/Eastern
date_default_timezone_set( 'US/Eastern' );
}
// Will return the number of days between the two dates passed in
function count_days( $a, $b )
{
// First we need to break these dates into their constituent parts:
$gd_a = getdate( $a );
$gd_b = getdate( $b );
// Now recreate these timestamps, based upon noon on each day
// The specific time doesn't matter but it must be the same each day
$a_new = mktime( 12, 0, 0, $gd_a['mon'], $gd_a['mday'], $gd_a['year'] );
$b_new = mktime( 12, 0, 0, $gd_b['mon'], $gd_b['mday'], $gd_b['year'] );
// Subtract these two numbers and divide by the number of seconds in a
// day. Round the result since crossing over a daylight savings time
// barrier will cause this time to be off by an hour or two.
return round( abs( $a_new - $b_new ) / 86400 );
}
// Prepare a few dates
$date1 = strtotime( '12/3/1973 8:13am' );
$date2 = strtotime( '1/15/1974 10:15pm' );
$date3 = strtotime( '2/14/2005 1:32pm' );
// Calculate the differences, they should be 43 & 11353
echo "<p>There are ", count_days( $date1, $date2 ), " days.</p>\n";
echo "<p>There are ", count_days( $date2, $date3 ), " days.</p>\n";
?>