按两个不同的键或值对多维数组排序

Question

This example depends on two keys/values instead of just one unlike many other examples I've seen in Stack-overflow. Apart from sorting array below by primary key, I also would like to sort it by age key so that I can achieve EXPECTED RESULT below. How should I modify CODE below to achieve it? CURRENT RESULT has A-6-6 key misplaced because my code doesn't handle it yet.

ORIGINAL ARRAY

$myarray = [
    'Z-9-0' => [
        'primary' => true,
        'age' => 55
    ],
    'C-7-1' => [
        'primary' => false,
        'age' => 60
    ],
    'K-1-9' => [
        'primary' => true,
        'age' => 60
    ],
    'C-2-1' => [
        'primary' => false,
        'age' => 40
    ],
    'F-6-6' => [
        'primary' => true,
        'age' => 60
    ],
    'A-6-6' => [
        'primary' => true,
        'age' => 30
    ]
];

EXPECTED RESULT

(
    [F-6-6] => Array
        (
            [primary] => 1
            [age] => 60
        )
    [K-1-9] => Array
        (
            [primary] => 1
            [age] => 60
        )
    [Z-9-0] => Array
        (
            [primary] => 1
            [age] => 55
        )
    [A-6-6] => Array
        (
            [primary] => 1
            [age] => 30
        )
    [C-7-1] => Array
        (
            [primary] => 
            [age] => 60
        )
    [C-2-1] => Array
        (
            [primary] => 
            [age] => 40
        )
)

CODE

uasort($myarray, function($a, $b) {
    return strcmp($b['primary'], $a['primary']);
});

print_r($org);

CURRENT RESULT

As you can see, A-6-6 is not in right place compared to expected result above. So the bigger the age the higher place it should appear.

(
    [A-6-6] => Array
        (
            [primary] => 1
            [age] => 30
        )
    [F-6-6] => Array
        (
            [primary] => 1
            [age] => 60
        )
    [K-1-9] => Array
        (
            [primary] => 1
            [age] => 60
        )
    [Z-9-0] => Array
        (
            [primary] => 1
            [age] => 55
        )
    [C-7-1] => Array
        (
            [primary] => 
            [age] => 60
        )
    [C-2-1] => Array
        (
            [primary] => 
            [age] => 40
        )
)

Answer 1

I think you can add an extra check for the 'age' key in the uasort when the values for the 'primary' key are equal'.

uasort($myarray, function($a, $b) {
    if ($b['primary'] === $a['primary']) {
        return $b['age'] > $a['age'];
    }
    return strcmp($b['primary'], $a['primary']);
});

Demo