PHP按项目数排序多维数组

Question

我有一个数组,如:

Array
(
    [DEF] => Array
        (
            [0] => Array
                (
                    [type] => 1
                    [id] => 1212
                    [name] => Jane Doe
                    [current] => 1
                )

            [1] => Array
                (
                    [type] => 1
                    [id] => 3123121
                    [name] => Door
                    [current] => 
                )
        )

    [ABC] => Array
        (
            [0] => Array
                (
                    [type] => 1
                    [id] => 1234
                    [name] => John Doe
                    [current] => 
                )
        )

    [WW] => Array
        (
            [0] => Array
                (
                    [type] => 1
                    [id] => 1212
                    [name] => Jane Doe
                    [current] => 1
                )

            [1] => Array
                (
                    [type] => 1
                    [id] => 3123121
                    [name] => Door
                    [current] => 
                )

            [2] => Array
                (
                    [type] => 1
                    [id] => 64646
                    [name] => Floor
                    [current] => 
                )
        )
)

并且我想按内部数组项的数字(count())对这个数组进行排序(即大多数项目是第一个),所以我将拥有这个数组:

Array
(
    [WW] => Array
        (
            [0] => Array
                (
                    [type] => 1
                    [id] => 1212
                    [name] => Jane Doe
                    [current] => 1
                )

            [1] => Array
                (
                    [type] => 1
                    [id] => 3123121
                    [name] => Door
                    [current] => 
                )

            [2] => Array
                (
                    [type] => 1
                    [id] => 64646
                    [name] => Floor
                    [current] => 
                )
        )

    [DEF] => Array
        (
            [0] => Array
                (
                    [type] => 1
                    [id] => 1212
                    [name] => Jane Doe
                    [current] => 1
                )

            [1] => Array
                (
                    [type] => 1
                    [id] => 3123121
                    [name] => Door
                    [current] => 
                )
        )

    [ABC] => Array
        (
            [0] => Array
                (
                    [type] => 1
                    [id] => 1234
                    [name] => John Doe
                    [current] => 
                )
        )
)

任何人都可以建议一个有效的方法吗？谢谢.

Answer 1

使用uksort:

uksort($array, function($a, $b) { return count($b) - count($a); });

使用array_multisort:

array_multisort(array_map('count', $array), SORT_DESC, $array);

PHP <5.3:

function sort_cb($a, $b) {
    return count($b) - count($a);
}
uksort($array, 'sort_cb');