Sorting order items via a hooked function in WooCommerce

Question

In WooCommerce, I have a product attribute pa_location for "location" with which I sort my order items. When order items have the same location, I'd like to sort them by SKU. So, sort first by location and then by SKU.

I looked to "PHP usort sorting multiple fields" but I am unable to figure out how it applies and would work for my function.

I have this custom function that works to sort by pa_location, but cannot get it to also sort by _sku.

I tried implementing some of the examples in the referenced post about sorting.

add_filter( 'woocommerce_order_get_items', function( $items, $order ) {

    uasort( $items,
        function( $a, $b ) {
            return strnatcmp( $a['pa_location'], $b['pa_location'] );
        }
    );

    return $items;
}, 10, 2 );

I hope to sort by location then by SKU using this function. Right now it is only sorting by location.

Answer 1

Try the following based on "PHP usort sorting multiple fields" answers thread:

add_filter( 'woocommerce_order_get_items', 'filter_order_get_items_callback', 10, 2 );
function filter_order_get_items_callback( $items, $order ) {
    uasort( $items,
        function( $a, $b ) {
            if( $a['pa_location'] == $b['pa_location'] ) {
                return strcmp( $a['_sku'], $b['_sku'] );
            }
            return strnatcmp( $a['pa_location'], $b['pa_location'] );
        }
    );

  return $items;

}

---

TESTING:

$items = array (
    0 => array ( 'pa_location' => 'Marseille',
        '_sku' => '27458C' ),
    1 => array ( 'pa_location' => 'Nice',
        '_sku' => '32458A' ),
    2 => array ('pa_location' => 'Cannes',
        '_sku' => '35C7L5' ),
    3 => array ('pa_location' => 'Marseille',
        '_sku' => '387B85'),
    4 => array ( 'pa_location' => 'Cannes',
        '_sku' => '25A587' )
);

uasort( $items, function( $a, $b ) {
    if( $a['pa_location'] == $b['pa_location'] ) {
        return strcmp( $a['_sku'], $b['_sku'] );
    }
    return strnatcmp( $a['pa_location'], $b['pa_location'] );
} );
// Raw output
echo '<pre>'; print_r( $items ); echo '<pre>';

We get this output:

Array
(
    [2] => Array
        (
            [pa_location] => Cannes
            [_sku] => 25A587
        )
    [4] => Array
        (
            [pa_location] => Cannes
            [_sku] => 35C7L5
        )
    [0] => Array
        (
            [pa_location] => Marseille
            [_sku] => 27458C
        )
    [3] => Array
        (
            [pa_location] => Marseille
            [_sku] => 387B85
        )
    [1] => Array
        (
            [pa_location] => Nice
            [_sku] => 32458A
        )
)

Which is what we expect, sorting first pa_location and after _sku.