添加每个月的正确天数

Question

Using the following function I can display the years and months between two dates, but how can I add the correct days for each month as another array within each month? I can't just add the days manually as I need it to account for leap years etc.

function yearMonth($start_date, $end_date)
{
    $begin = new DateTime( $start_date );
    $end = new DateTime( $end_date);
    $interval = new DateInterval('P1M'); // 1 month interval

    $period = new DatePeriod($begin, $interval, $end);

    foreach ( $period as $dt )
        $years[$dt->format( "Y" )][] = $dt->format( "F" );

    return $years;
}

$list  =  yearMonth("2007-03-24", "2009-06-26");
var_dump($list);

Answer 1

Since nobody else answered:

function yearMonth($start_date, $end_date)
{
$begin = new DateTime( $start_date );
$end = new DateTime( $end_date);
$interval = new DateInterval('P1D'); // 1 month interval

$period = new DatePeriod($begin, $interval, $end);

$lastMonth = null;
$lastYear = null;
$aResult = array();
foreach ( $period as $dt )
{
    if ($dt->format('Y') != $lastYear)
    {
        $lastYear = $dt->format('Y');
    }
    if ($dt->format('F') != $lastMonth)
    {
        $lastMonth = $dt->format('F');
    }
    if (!isset($aResult[$lastYear]))
    {
        $aResult[$lastYear] = array();
    }
    if (!isset($aResult[$lastYear][$lastMonth]))
    {
        $aResult[$lastYear][$lastMonth] = array();
    }
    $aResult[$lastYear][$lastMonth][] = $dt->format('d');
}

return $aResult;
}  

On a side note I am planing to create a sort of Gantt chart style flat layout in table format of the years, months and days between dates. Do you think this is a suitable way of generating that? Or is there a better way?