通过包含数字和字母的两个值对多维数组进行排序

I have an array which looks like

[0] => Array
    (
        [typeName] => Element
        [quantity] => 35
        [flag] => 4
    )

I already found a way by using usort() to sort an array by its sub elements. Which works great for numeric values.

public static function _sortByAmount($a, $b) {
        return $b['quantity'] - $a['quantity'];
}

From time to time, it could happen that I have more than one array elements with the same quantity. Those entries should be sorted by the Name too. In the end, the array should look like this.

[0] => Array
    (
        [typeName] => Element
        [quantity] => 567
        [flag] => 4
    )
[1] => Array
    (
        [typeName] => aaa-element
        [quantity] => 35
        [flag] => 4
    )
[2] => Array
    (
        [typeName] => bbb-element
        [quantity] => 35
        [flag] => 4
     )
[3] => Array
    (
        [typeName] => Element
        [quantity] => 10
        [flag] => 4
    )

Is it possible to extend my function somehow?

You can check anything you want in your compare function. For example, if quantity == quantity then return strcmp.

public static function _sortByAmount($a, $b) {
    if($b['quantity'] == $a['quantity']){
        return strcmp($a['typeName'], $b['typeName']);
    } else {
        return $b['quantity'] - $a['quantity'];
    }
}

you can also use strcasecmp if you want the check to be case insensitive.

not sure, but

public static function _sortByAmount($a, $b) {
        $byQuantity = $a['quantity'] - $b['quantity'];
        return $byQuantity ?: strcmp($a['typeName'], $b['typeName']);
}