PHP strtotime giving the wrong date for certain months

Question

the following code.

strtotime("first saturday", strtotime("+2 month"));

Is working correctly but with the months of April +2 month, October + 8 month, and December + 10 month is giving the second saturday in that month not the first.

Any ideas what is causing it and how to stop it.

Marvellous

what you get if u do strtotime("first saturday", strtotime("1 April 2011")); — Haim Evgi, Feb 02 '11 at 15:38

score 5 · Accepted Answer · answered Feb 02 '11 at 15:43

5

$saturday = strtotime("first saturday", strtotime("+2 month", strtotime(date("01-m-Y"))));

answered Feb 02 '11 at 15:43

butterbrot

980
6
10

Marvellous. Simple and effective just what I wanted. – Walrus Feb 02 '11 at 15:53
@butterbrot If `strtotime("+2 month", strtotime(date("01-m-Y")))` is a Saturday, **you're still going to get the next**. – Linus Kleen Feb 02 '11 at 15:56
true, strtotime("first saturday", strtotime("+2 month", strtotime(date("01-m-Y")))-1); will that do? – butterbrot Feb 02 '11 at 16:01
@butterbrot No. This, too, can be a saturday. You'll need to check if `"+2 month"` is a saturday first. Like in my answer... – Linus Kleen Feb 02 '11 at 16:03
@linus no not sure, if `strtotime("+2 month", strtotime(date("01-m-Y")))-1` is a saturday as well, it is the wrong saturday as it is in the pref month, and we care about the next month. (?) – butterbrot Feb 02 '11 at 16:09
having said that, this should probably work too: `strtotime("first saturday", strtotime("+2 month last day", $now))` – butterbrot Feb 02 '11 at 16:25

Linus Kleen · Answer 2 · 2011-02-02T16:08:07.153

This is because "first saturday" is calculate from the date given. If given date already is a saturday, the next one is calculated.

If you need the first saturday from a specific month, do:

$stamp = time();
$tm = localtime($stamp, TRUE);

// +1 to account for the offset, +2 for "+2 month"
$begin = mktime(0, 0, 0, $tm['tm_mon'] + 1 + 2, 1, 1900 + $tm['tm_year']);

if (6 == $begin['tm_wday']) {
//  we already got the saturday
    $first_saturday = $stamp;
} else {
    $first_saturday = strtotime('first saturday', $begin);
}

score 0 · Answer 3 · answered Feb 02 '11 at 15:45

Use the first day of the month to create your origin timestamp, and then just check the month/year:

function firstSaturday($month, $year) {
    if (!is_numeric($month) && !is_numeric($year)) {
        return -1;
    }

    return strtotime('first saturday', mktime(0, 0, 0, $month, 1, $year));
}

PHP strtotime giving the wrong date for certain months

3 Answers3