应该是新月的增加日期

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?

Answer 1

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');
}