Reputation: 976
I'm using the below calculator to determine the years, months, and days between a set date and the current date. I thought it was working fine, but then it came up on the year mark and i noticed it was not working properly. Tomorrow is actually when the one year mark would be, but it is currently returning 11 months, 34 days
. Could anyone tell me whats wrong? It should be 11 months, 30 days
.
function relationshipTimer($functionDate)
{
$date1 = $functionDate;
$date2 = date("Y-m-d");
$diff = abs(strtotime($date2) - strtotime($date1));
$years = floor($diff / (365 * 60 * 60 * 24));
$months = floor(($diff - ($years * 365 * 60 * 60 * 24)) / ((365 * 60 * 60 * 24) / 12));
$days = floor(($diff - $years * 365 * 60 * 60 * 24 - $months * 30 * 60 * 60 * 24) / (60 * 60 * 24));
if ($years > 0) {echo $years . " Year";}
if ($years > 1) {echo "s ";}
if ($months > 0) {echo " " . $months . " Month";}
if ($months > 1) {echo "s ";}
if ($date1 == $date2) {echo "1 Day ";}
if ($days > 0) {echo $days . " Day";}
if ($days > 1) {echo "s ";}
}
And this is where $functionDate comes from:
relationshipTimer("2018-04-28");
Upvotes: 2
Views: 65
Reputation: 6144
When you calculate $days
, you are assuming that all months are 30 days long, which is obviously wrong. Therefore you get a year that is 11 months plus 35 days (36 days for leap years).
Processing dates is complicated. You should always use specialized tools like PHP's DateTime::diff()
For example, with:
$date1 = new DateTime("2018-04-28");
$date2 = new DateTime("2019-04-27");
$diff = $date2->diff($date1);
print $diff->format("%y years %m months %d days\n");
... you get (because April has 30 days):
0 years 11 months 29 days
Upvotes: 5