重构数组在PHP中

Question

I have the following source array which I'm trying to restructure using group_name to give me the require output below.

Any help or pointers appreciated. Thanks, Lk

Source:

Array
(
[field_a] => Array
    (
        [type] => text
        [group_name] => 
    )

[field_b] => Array
    (
        [type] => number_integer
        [group_name] => group_other
    )

[field_c] => Array
    (
        [type] => text
        [group_name] => 
    )

[field_d] => Array
    (
        [type] => link
        [group_name] => group_web_links
    )

[field_e] => Array
    (
        [type] => link
        [group_name] => group_web_links
    )

[field_f] => Array
    (
        [type] => text
        [group_name] => group_web_links
    )

)

Output:

Array
(
[group_other] => Array
    (
        [field_b] => Array
           (
               [type] => number_integer
               [group_name] => group_other
           )
    )

[group_web_links] => Array
    (
        [field_d] => Array
            (
                [type] => link
                [group_name] => group_web_links
            )

        [field_e] => Array
            (
                [type] => link
                [group_name] => group_web_links
            )

        [field_f] => Array
            (
                [type] => text
                [group_name] => group_web_links
            )
    )

[field_a] => Array
    (
        [type] => text
        [group_name] => 
    )

[field_c] => Array
    (
        [type] => text
        [group_name] => 
    )
)

Answer 1

If key order of new array is not so important:

$new_array = array();
foreach ($old_array as $key => $value) {
    if (empty($value['group_name'])) $new_array[$key] = $value;
    else {
        if (!array_key_exists($value['group_name'], $new_array) $new_array[$value['group_name']] = array();
        $new_array[$value['group_name']][$key] = $value;
    }
}