你也可以看看DatePeriod类:

$period = new DatePeriod(
     new DateTime('2010-10-01'),
     new DateInterval('P1D'),
     new DateTime('2010-10-05')
);

这将为您提供一个包含DateTime对象的数组。

迭代

foreach ($period as $key => $value) {
    //$value->format('Y-m-d')       
}

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

function datesbetween ($date1,$date2)
{
    $dates= array();
    for ($i = $date1
       ; $i<= $date1
       ; $i=date_add($i, date_interval_create_from_date_string('1 days')) ) 
    {            
       $dates[] = clone $i;
    }
    return $dates;
}

// Specify the start date. This date can be any English textual format  
$date_from = "2018-02-03";   
$date_from = strtotime($date_from); // Convert date to a UNIX timestamp  

// Specify the end date. This date can be any English textual format  
$date_to = "2018-09-10";  
$date_to = strtotime($date_to); // Convert date to a UNIX timestamp  

// Loop from the start date to end date and output all dates inbetween  
for ($i=$date_from; $i<=$date_to; $i+=86400) {  
    echo date("Y-m-d", $i).'<br />';  
} 

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

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);