Sorting a collection in different orders based on conditional for column value (PHP / Laravel)

Question

Basically I have a collection of products, which all have location codes.

These codes start with W1 or W2 or W3, followed by another letter and some numbers (irrelevant beyond the third character for this problem)

So for example: W1A..., W1B..., W2P..., W2Z...

Now the thing is I want to sort the products in a specific order depending on the location codes.

The order should be W2 first, but in the order of W2Z... to W2A..., and after that comes W1, in order of W1A... to W1Z..., and after that W3 in W3A... to W3Z...

How could I write a custom sort function / query that achieves this order of the products, based on the string value of their location?

You can use [`sort`](https://laravel.com/docs/8.x/collections#method-sort) with a callback. The callback is described [here](https://www.php.net/manual/en/function.uasort.php#refsect1-function.uasort-parameters). Give it a try and if you have problems still then share what you tried — apokryfos, Jan 28 '22 at 22:42

IGP · Answer 1 · 2022-01-28T23:09:11.263

That can be easily achieved by passing a closure to a sort function. The spaceship operator (<=>) also helps a lot.

There is an example in the documentation.

This could work:

$products->sortBy([
    // sort the second character using a specific order (2, 1, 3)
    function ($a, $b) {
        $order = ['2' => 1, '1' => 2, '3' => 3];
        return $order[$a->code[1]] <=> $order[$b->code[1]];
    },
    // sort the third character in descending order (Z to A) if second character is 2. Ascending order otherwise
    function ($a, $b) {
        return ($a->code[1] === '2' && $b->code[1] === '2')
            ? $b->code[2] <=> $a->code[2]
            : $a->code[2] <=> $b->code[2];
    }
]);

Sorting a collection in different orders based on conditional for column value (PHP / Laravel)

1 Answers1