Counting days "forgets" last day - php

Question

i'm using this code and it works fine so far:
<?php
$start = (new DateTime('2019-02-11'));
$end = (new DateTime('2019-04-23'));
$months = new DatePeriod($start, DateInterval::createFromDateString('1 month'), $end);
$days = new DatePeriod($start, DateInterval::createFromDateString('1 day'), $end);
echo "<table border=1><tr>";
foreach ($months as $month){
echo "<td>".$month->format("M");
foreach ($days as $day)
{
if($month->format("M")==$day->format("M")){$d++;}
}
echo " (".$d." days)</td>";
unset($d);
}
echo "</tr></table>";
?>
The output is:
Feb (18 days) Mar (31 days) Apr (22 days)
Unfortunately it "forgots" the last day of April in some way (must be 23 days like stated in $end).
Why does the code not count/include the last day?
Do i need to add something like "plus 1 day" to the $end date?
Thank you guys!

Answer 1

Your end date has timestamp 00:00:00 which means, according to the DateTime interval object, the day hasn't actually started yet. If you change your $end to $end = (new DateTime('2019-04-23 01:00:00')); it will include that day as well.
Also you should probably add $d = 0; in your foreach loop for months. Right now you don't define it. (Which defaults it to 0, so it still works. But it's better to define it yourself.)

Answer 2

I have to disagree with Dirks answer. Using \DateTime a day starts at zero (00:00:00).
Testable with:
<?php
$start = new \DateTimeImmutable('2019-02-10 23:59:57');
for ($i = 0; $i < 7; ++$i) {
echo $start->format('c'), "\n";
$start = $start->modify('+1 second');
}
Which shows (for my timezone):
2019-02-10T23:59:57+01:00
2019-02-10T23:59:58+01:00
2019-02-10T23:59:59+01:00
2019-02-11T00:00:00+01:00
2019-02-11T00:00:01+01:00
2019-02-11T00:00:02+01:00
2019-02-11T00:00:03+01:00
https://3v4l.org/8Q3kb
The problem with your code, is that \DatePeriod excludes the end date. And as such the inner loops runs a day short.
<?php
$start = new \DateTimeImmutable('2019-02-11');
$end = $start->modify('+3 days');
$period = new \DatePeriod($start, new \DateInterval('P1D'), $end);
foreach ($period as $date) {
echo $date->format('c'), "\n";
}
echo 'actual end date: ', $end->format('c');
# 2019-02-11T00:00:00+01:00
# 2019-02-12T00:00:00+01:00
# 2019-02-13T00:00:00+01:00
# actual end date: 2019-02-14T00:00:00+01:00
But overall the approach is a bit excessive. For example, the following gives the same results with (imo) better semantics and only a minimum of looping:
<?php
/**
* #param DateTimeImmutable $start
* #param DateTimeImmutable $end
*
* #return Generator
*/
function remainingDaysPerMonthBetween(\DateTimeImmutable $start, \DateTimeImmutable $end): \Generator {
while ($start < $end) {
$diff = $start->diff(min(
$start->modify('last day of this month'),
$end
));
yield [$start, $diff->days];
$start = $start->modify('first day of next month');
}
}
$start = new \DateTimeImmutable('2019-02-11');
$end = new \DateTimeImmutable('2019-04-23');
foreach (remainingDaysPerMonthBetween($start, $end) as [$date, $remainingDays]) {
printf("%s: %d\n", $date->format('M'), $remainingDays + 1);
}
https://3v4l.org/BCAYq