Next month, same day in PHP

Question

I got a last time (and urgent) requeriment of an "event" that needs to be scheduled the same day of every month.

Say of you set the start date on the 1st May you should get the next events on the 1st of Jun, 1 Jul etc. The problem comes with a start date on the 31st (the next ones could be 30 or 28 depending on the month)

Considering that there are months with different numbers of days (28,30,31) depending on the month itself and the year... what would ba an easy way to setup this?

Consider the following (and flawed) nextmonth function:

$events = array()

function nextmonth($date) {
   return $date+(60*60*24*30);
}
$curr = $start;
while($curr < $end) {
    $events[ = $curr;
    $curr = nextmonth($curr);
}

Edited to add: The problem for me is, simply enought, is to solve what the number of days of any given month is and thus get the next corresponding date..

Answer 1

Since months are so varied in size, wouldn't the best way to set the next month be something like: this day, next month except if this day doesn't exist next month.

Example:

June 5, 2009, next month would be July 5, 2009
August 31, 2009, next month would be September 30, 2009

or simply, strtotime("+1 month")

Answer 2

I recommend reading the following comment on php.net. strtotime() (php.net)

Edit: The next answer gives the "summary" of the link I posted for those not able to decipher the content shown there.

Answer 3

Update:

This will give you the number of days in given month:

echo date('t', $timestamp);

See: date()

Old answer:

I'm not sure about the algorithm you're thinking of but I believe this will help you:

echo date('d-M-y', strtotime('next month'));

Answer 4

This will return proper timestamp for $X months ahead: mktime(0,0,0,date("m")+$X,date('d'),date("Y"));

Answer 5

How about this function:

    function getNextMonthN($date, $n = 1) {
      $newDate = strtotime('+' . $n . ' months', $date);
      if (date('j', $date) !== (date('j', $newDate))) {
     $newDate = mktime(0, 0, 0, date('n', $newDate), 0, date('Y', $newDate));
      }
      return $newDate; 
    }

There is another solution on the php.net manual site under the strtotime entry in the comments.

Answer 6

Tried this as a lark, and it actually works

strtotime('last day next month')

So :

$today_next_month = strtotime('this day next month');
$last_day_next_month = strtotime('last day next month');
if (date('d', $today_next_month) < date('d', $last_day_next_month)){
    $date = date('m-d-Y', $last_day_next_month); 
} else {
    $date = date('m-d-Y', $today_next_month);
}
echo "And the winner is : $date<br/>";