如何在PHP中按日期间隔对数组进行排序

Question

I have an array that contains date values. I want to sort this array by date, where the date is near(+/-1 days) from now date. The array is in this format:

Array
(
   [0] => Array
    (
        [id] => 4197
        [date] => Wed, 19 Sep 2015 17:00:00 +0000
    )
    [1] => Array
        (
            [id] => 4192
            [date] => Sun, 13 Sep 2015 17:00:00 +0000
        )
    [2] => Array
        (
            [id] => 4189
            [date] => Sat, 29 Aug 2015 20:00:00 +0000
        )
    [3] => Array
        (
            [id] => 4173
            [date] => Wed, 09 Sep 2015 16:00:00 +0000
        )
)

I want to get the array sorted in this way:

Array
(
   [0] => Array
    (
            [id] => 4173
            [date] => Wed, 09 Sep 2015 16:00:00 +0000
    )
    [1] => Array
        (
            [id] => 4192
            [date] => Sun, 13 Sep 2015 17:00:00 +0000
        )
    [2] => Array
        (
            [id] => 4197
            [date] => Wed, 19 Sep 2015 17:00:00 +0000
        )
    [3] => Array
        (
            [id] => 4189
            [date] => Sat, 29 Aug 2015 20:00:00 +0000
        )
)

I tried this solution:

function sortFunction( $a, $b ) {
    $now = strtotime("+1 day");
    if (($now - strtotime($a["date"])>0) && ($now - strtotime($b["date"])<0))
     {return 0;}
    return strtotime($b["date"]) - strtotime($a["date"]);
}
usort($array, "sortFunction");

what I'm doing wrong. Thanks

Answer 1

Assuming all of inner arrays have a date property with the value formatted consistently, the following solution works:

usort($array, function($dateArray1, $dateArray2) {

        $now = new \DateTime();

        $dateA = new \DateTime($dateArray1['date']);
        $dateB = new \DateTime($dateArray2['date']);

        $dayDifferenceA = abs($dateA->diff($now)->days);
        $dayDifferenceB = abs($dateB->diff($now)->days);

        if($dayDifferenceA == $dayDifferenceB) {
            return 0;
        }

        return ($dayDifferenceA < $dayDifferenceB) ? -1 : 1;
    });

More checks should be added to ensure date calculations produce correctly formatted results throughout but this is the code in its most basic form.