在 PHP 中按键长度（值中的键长度）对数组进行降序排序

Question

My question is an extension/variation on this already well-answered question :

There is an array with binary-looking keys:

    codeWords = [
        '000111' => [6, 1, 0, 't'],
        '1110' => [4, 6, 0, 't'],
        '10011' => [5, 8, 0, 't'],
        '001000' => [6, 12, 0, 't'],
        '00110101' => [8, 0, 0, 't'],
        '010' => [3, 1, 1, 't'],
        '10' => [2, 3, 1, 't'],
        '011' => [3, 4, 1, 't'],
        '0010' => [4, 6, 1, 't'],
        '00011' => [5, 7, 1, 't'],
        '000101' => [6, 8, 1, 't'],
    ];

I need this array ordered like this:

    $codeWords = [
        '00110101' => [8, 0, 0, 't'],
        '001000' => [6, 12, 0, 't'],
        '000111' => [6, 1, 0, 't'],
        '000101' => [6, 8, 1, 't'],
        '10011' => [5, 8, 0, 't'],
        '00011' => [5, 7, 1, 't'],
        '1110' => [4, 6, 0, 't'],
        '0010' => [4, 6, 1, 't'],
        '011' => [3, 4, 1, 't'],
        '010' => [3, 1, 1, 't'],
        '10' => [2, 3, 1, 't'],
    ];

This solution is working fine:

    uksort($codeWords, function($a, $b) {
        return strlen($a) < strlen($b);
    });

but...

...key length is already stored in value[0] . Therefore, strlen() does not have to be used in the comparison function.

I have tried to adapt some of the solutions given in the linked question accordingly with using value[0] - but do not come to the desired result.

Can someone get me on the right track?

Answer 1

The uksort function specifically uses array keys, and thus your code return $a[0] < $b[0]; compares only first symbols of your 0010101 keys.

You need uasort .

    uasort($codeWords, function($a, $b) {
        return $b[0] - $a[0];
    });