按最高值對數組中的對象進行排序

Question

我有一個foreach循環，可找到評論答復並將其存儲在$child_comments

后

<?php  echo '<pre>';
print_r($child_comments);
echo '</pre>'; ?>

我為每個父注釋得到一個單獨的數組：

Array
(
    [0] => stdClass Object
        (
            [comment_ID] => 603
            [comment_parent] => 600
            [user_id] => 2
        )

    [1] => stdClass Object
        (
            [comment_ID] => 601
            [comment_parent] => 600
            [user_id] => 2
        )

)

Array
(
     [0] => stdClass Object
        (
            [comment_ID] => 584
            [comment_parent] => 580
            [user_id] => 1
        )
)

Array
(
    [0] => stdClass Object
        (
            [comment_ID] => 608
            [comment_parent] => 520
            [user_id] => 2
        )

    [1] => stdClass Object
        (
            [comment_ID] => 598
            [comment_parent] => 520
            [user_id] => 2
        )

    [2] => stdClass Object
        (
            [comment_ID] => 521
            [comment_parent] => 520
            [user_id] => 2
        )

)

但是我需要按其評論ID（從最高ID到最低ID）對評論進行排序和輸出。

我可以得到我喜歡的評論

foreach ($child_comments as $objects) {
  echo $objects->comment_ID;
}

但它們仍將按照其父注釋進行排序。 有任何想法嗎？ 理想的結構如下所示：

Array
(
    [0] => stdClass Object
        (
            [comment_ID] => 608
            [comment_parent] => 520
            [user_id] => 2
        )
    [1] => stdClass Object
        (
            [comment_ID] => 603
            [comment_parent] => 600
            [user_id] => 2
        )

    [2] => stdClass Object
        (
            [comment_ID] => 601
            [comment_parent] => 600
            [user_id] => 2
        )

    [3] => stdClass Object
        (
            [comment_ID] => 598
            [comment_parent] => 520
            [user_id] => 2
        )

    [4] => stdClass Object
        (
            [comment_ID] => 584
            [comment_parent] => 580
            [user_id] => 1
        )

    [5] => stdClass Object
        (
            [comment_ID] => 521
            [comment_parent] => 520
            [user_id] => 2
        )
)

Answer 1

如果您在不同的arrays獲得每個comments ，則可以先使用array_merge（）創建單個數組，然后使用usort（） sort最終數組進行sort例如，

<?php
    $comments=array_merge($child_comments);
    function cmp($a, $b) {
        return $b['comment_ID'] - $a['comment_ID'];//use $b->comment_ID if Object
    }
    usort($comments, "cmp");
    print_r($comments);
?>

Answer 2

如果您有復雜的排序標准，最好的方法是使用usort進行回調。

例如：

usort($arrayOfObjects, function($a, $b){
    if($a->comment_parent > $b->comment_parent) return 1;
    elseif($a->comment_parent < $b->comment_parent) return -1;
    else{
        // Do child compare here...
    }
});