你必须添加$end->modify('+1 day')来包含间隔的最后一天，例如，如果不使用modify()方法，一月份将有31天而不是30天。 这个版本的代码将包括间隔的最后一天:

$begin = new DateTime( '2018-08-01' );
$end = new DateTime( '2018-08-31' );
$end = $end->modify( '+1 day' ); 

$interval = new DateInterval('P1D');
$daterange = new DatePeriod($begin, $interval ,$end);

foreach($daterange as $date){
    echo $date->format("Ymd") . "<br>";
}

PHP文档链接

<?
print_r(getDatesFromRange( '2010-10-01', '2010-10-05' ));

function getDatesFromRange($startDate, $endDate)
{
    $return = array($startDate);
    $start = $startDate;
    $i=1;
    if (strtotime($startDate) < strtotime($endDate))
    {
       while (strtotime($start) < strtotime($endDate))
        {
            $start = date('Y-m-d', strtotime($startDate.'+'.$i.' days'));
            $return[] = $start;
            $i++;
        }
    }

    return $return;
}

function createDateRangeArray($strDateFrom,$strDateTo)
{
    // takes two dates formatted as YYYY-MM-DD and creates an
    // inclusive array of the dates between the from and to dates.

    // could test validity of dates here but I'm already doing
    // that in the main script

    $aryRange = [];

    $iDateFrom = mktime(1, 0, 0, substr($strDateFrom, 5, 2), substr($strDateFrom, 8, 2), substr($strDateFrom, 0, 4));
    $iDateTo = mktime(1, 0, 0, substr($strDateTo, 5, 2), substr($strDateTo, 8, 2), substr($strDateTo, 0, 4));

    if ($iDateTo >= $iDateFrom) {
        array_push($aryRange, date('Y-m-d', $iDateFrom)); // first entry
        while ($iDateFrom<$iDateTo) {
            $iDateFrom += 86400; // add 24 hours
            array_push($aryRange, date('Y-m-d', $iDateFrom));
        }
    }
    return $aryRange;
}

来源:http://boonedocks.net/mike/archives/137-Creating-a-Date-Range-Array-with-PHP.html

请注意，ViNce提供的答案不包括期间的结束日期。

如果你使用的是PHP 5.3+，你最好使用这样的函数:

/**
 * Generate an array of string dates between 2 dates
 *
 * @param string $start Start date
 * @param string $end End date
 * @param string $format Output format (Default: Y-m-d)
 *
 * @return array
 */
function getDatesFromRange($start, $end, $format = 'Y-m-d') {
    $array = array();
    $interval = new DateInterval('P1D');

    $realEnd = new DateTime($end);
    $realEnd->add($interval);

    $period = new DatePeriod(new DateTime($start), $interval, $realEnd);

    foreach($period as $date) { 
        $array[] = $date->format($format); 
    }

    return $array;
}

然后，你可以像预期的那样调用函数:

getDatesFromRange('2010-10-01', '2010-10-05');

运行演示

关于DatePeriod类的注意:您可以使用DatePeriod的第4个参数来排除开始日期(DatePeriod::EXCLUDE_START_DATE)，但此时不能包括结束日期。

下面是一个函数，它将从两个方向返回日期范围，适用于PHP >=5.2.2:

function createRange($start, $end, $format = 'Y-m-d') {
    $start  = new DateTime($start);
    $end    = new DateTime($end);
    $invert = $start > $end;

    $dates = array();
    $dates[] = $start->format($format);
    while ($start != $end) {
        $start->modify(($invert ? '-' : '+') . '1 day');
        $dates[] = $start->format($format);
    }
    return $dates;
}

使用的例子:

print_r(createRange('2010-10-01', '2010-10-05'));
/*Array
(
    [0] => 2010-10-01
    [1] => 2010-10-02
    [2] => 2010-10-03
    [3] => 2010-10-04
    [4] => 2010-10-05
)*/

print_r(createRange('2010-10-05', '2010-10-01', 'j M Y'));
/*Array
(
    [0] => 5 Oct 2010
    [1] => 4 Oct 2010
    [2] => 3 Oct 2010
    [3] => 2 Oct 2010
    [4] => 1 Oct 2010
)*/

demo

我认为这是最简短的答案

按照您的喜好编辑代码

for ($x=strtotime('2015-12-01');$x<=strtotime('2015-12-30');$x+=86400)
echo date('Y-m-d',$x);