PHP循环日期按月

Question

在这个日期数组上有一个 PEBKAC...我不明白为什么第二维的第一个位置会被日期的最后修改覆盖...非常感谢所有帮助！

$year=date('Y');
$count=date('m'); //loop from begining of current year to current month

$begin =new DateTime("$year-01-01");
$end = clone $begin;


for ($i=0; $i < $count; $i++){
    if ($i >0){ 
        $begin=$begin->add(new DateInterval('P1M'));
        $end = clone $begin;
    }
    $dateArray[$i][0]=$begin;
    $dateArray[$i][1]=$end->modify('last day of this month');
}

我正在寻找的输出是有一个多维数组，其中包含从当年到当月的每个月的第一个日期和最后一个日期。

Answer 1

您正在存储对$begin 的引用，然后在每个循环中更新$begin。将 $begin 分配给数组时克隆：

$dateArray[$i][0] = clone $begin;

Answer 2

$year  =date('Y');
$count =date('m'); //loop from begining of current year to current month

$begin = new DateTime("$year-01-01");
$end   = clone $begin;

for ($i=0; $i < $count; $i++){
    if ($i >0){ 
        $begin = $begin->add(new DateInterval('P1M'));
        $end   = clone $begin;
    }
    $dateArray[$i][0]=clone $begin;
    $dateArray[$i][1]=$end->modify('last day of this month');
}

将产生：

Array
(
[0] => Array
    (
        [0] => DateTime Object
            (
                [date] => 2018-01-01 00:00:00.000000
                [timezone_type] => 3
            )

        [1] => DateTime Object
            (
                [date] => 2018-01-31 00:00:00.000000
                [timezone_type] => 3
            )
    )
[1] => Array
    (
        [0] => DateTime Object
            (
                [date] => 2018-02-01 00:00:00.000000
                [timezone_type] => 3
            )

        [1] => DateTime Object
            (
                [date] => 2018-02-28 00:00:00.000000
                [timezone_type] => 3
            )
    )
[2] => Array
    (
        [0] => DateTime Object
            (
                [date] => 2018-03-01 00:00:00.000000
                [timezone_type] => 3
            )
        [1] => DateTime Object
            (
                [date] => 2018-03-31 00:00:00.000000
                [timezone_type] => 3
            )
    )
[3] => Array
    (
        [0] => DateTime Object
            (
                [date] => 2018-04-01 00:00:00.000000
                [timezone_type] => 3
            )
        [1] => DateTime Object
            (
                [date] => 2018-04-30 00:00:00.000000
                [timezone_type] => 3
            )
    )
[4] => Array
    (
        [0] => DateTime Object
            (
                [date] => 2018-05-01 00:00:00.000000
                [timezone_type] => 3
            )
        [1] => DateTime Object
            (
                [date] => 2018-05-31 00:00:00.000000
                [timezone_type] => 3
            )
    )
[5] => Array
    (
        [0] => DateTime Object
            (
                [date] => 2018-06-01 00:00:00.000000
                [timezone_type] => 3
            )
        [1] => DateTime Object
            (
                [date] => 2018-06-30 00:00:00.000000
                [timezone_type] => 3
            )
    )
[6] => Array
    (
        [0] => DateTime Object
            (
                [date] => 2018-07-01 00:00:00.000000
                [timezone_type] => 3
            )
        [1] => DateTime Object
            (
                [date] => 2018-07-31 00:00:00.000000
                [timezone_type] => 3
            )
    )
)