how to find the last monday of the month

Question

I\'m not sure how to go about this one. I\'m building a calendar in PHP and need users to be able to add a repeating event that follows the following rule:

Last [DOW

Answer 1

Here's an alternative:

 0)
                return 29;
            # or if year is divisible by 400
            if ($year % 400 == 0)
                return 29;
            return 28;
        case 4:
        case 6:
        case 9:
        case 11:
            return 30; 
        default:
            return 31;
    }
}

function lastDayOfWeek($month, $year, $dow) {
    $d = new DateTime();

    #Finding the last day of month
    $d = $d->setDate($year, $month, lastDayOfMonth($month, $year));

    #Getting the day of week of last day of month
    $date_parts = getdate($d->getTimestamp());

    $diff = 0;

    #if we can't find the $dow in this week... (cause it would lie on next month)
    if ($dow > $date_parts['wday']) {
        # ...we go back a week.
        $diff -= 7;
    }

    return $date_parts['mday'] + $diff + ($dow - $date_parts['wday']);  
}

# checking the algorithm for this month...
for ($i=0; $i < 7; $i++) {
    echo lastDayOfWeek(6,2011,$i) . "
";
}

?>