Increment date when it should be a new month

Question

I have a PHP script which records things based on the day. So it will have a weekly set of inputs you would enter.

I get the data correctly, but when i do $day ++; it will increment the day, going passed the end of the month without ticking the month.

example:

//12/29
//12/30
//12/31
//12/32
//12/33

Where it should look like

//12/29
//12/30
//12/31
//01/01
//01/02

My script is as follows:

$week = date ("Y-m-d", strtotime("last sunday"));
$day = $week;
$run = array(7);  //this is actually defined in the data posted to the script, which is pretty much just getting the value of the array index for the query string.
foreach( $run as $key=>$value)
{
    $num = $key + 1;
    $items[] = "($num, $user, $value, 'run', '$day')";
    echo "".$day;
    $day ++;
}

Should I be manipulating the datetime differently for day incrementations?

possible duplicate: http://stackoverflow.com/questions/2332681/add-number-of-days-to-a-date and that linked question has some code that will probably help you as well — EdgeCaseBerg, Dec 02 '15 at 16:11
I am trying to see this being the thing. it seems to set it correct and shows the `$day` as `2015-12-29` which makes sense, but it wont tick to the next month when incrementing.... So it will say: `2015-12-32` Its still a date object, so im not sure why it wont just work accordingly. — Fallenreaper, Dec 02 '15 at 16:15
`$day` is not a datetime, it is a string. So adding 1 to it is not going to give you the results you're looking for. — Sean Bright, Dec 02 '15 at 16:15
Try having a check that says something like: `$day == 30 ? $day = 1 : $day++;` — Can O' Spam, Dec 02 '15 at 16:16
what about something like: `$day = strtotime("+1 day", strtotime($day));` — Fallenreaper, Dec 02 '15 at 16:19

score 3 · Answer 1 · answered Dec 02 '15 at 16:23

3

You can use

$day = date("Y-m-d", strtotime($day . " +1 day"));

instead of

$day++;

See live demo in ideone

answered Dec 02 '15 at 16:23

huysentruitw

27,376
9
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Sean Bright · Accepted Answer · 2015-12-02T16:24:17.393

2

You refer to $day as a "datetime" but it is just a string - that is what date() returns. So when you do $day++ you are adding 1 to "2015-12-02". PHP will do everything it can to make "2015-12-02" into a number and then add 1 to it, which is not date math. Here is a simple example:

<?php
$name = "Fallenreaper1";
$name++;
echo $name
?>

This will output:

Fallenreaper2

This is how I would do it, using an appropriate data type (DateTime):

<?php
$day = new DateTime('last sunday');

$run = array(7);
foreach ($run as $key => $value) {
  $num = $key + 1;
  $dayStr = $day->format('Y-m-d');
  $items[] = "($num, $user, $value, 'run', '$dayStr')";
  echo $dayStr;
  $day->modify('+1 day');
}

edited Dec 02 '15 at 16:24

answered Dec 02 '15 at 16:18

Sean Bright

118,630
17
138
146

Im thinking this is more efficient than doing a bunch of `strtotime` then, right? – Fallenreaper Dec 02 '15 at 16:25
`modify()` is probably just calling `strtotime` under the hood, so I doubt it. – Sean Bright Dec 02 '15 at 16:27
ahh ok. I like both answers, just not sure which is "right" – Fallenreaper Dec 02 '15 at 16:27
My personal preference is to always use `DateTime` and friends when dealing with date/time manipulation. But to each their own. – Sean Bright Dec 02 '15 at 16:29
i thought i was using datetime, so i think this will be labelled as the correct answer, to make sure my code makes sense and is clean instead of looking like a datetime, but being a string. – Fallenreaper Dec 02 '15 at 16:30

score 0 · Answer 3 · answered Dec 02 '15 at 16:28

0

To increase time you should use strtotime("+1 day");

here is simple example of using it

<?php
$now_time = time();
for($i=1;$i<8;$i++) {
    $now_time = strtotime("+1 day", $now_time);
    echo date("Y-m-d", $now_time) . "<br>";
}
?>

answered Dec 02 '15 at 16:28

Fahed Alkaabi

269
2
10

Increment date when it should be a new month

3 Answers3