Question

Neither of these work… (nothing is sorted)

I adapted these from an example on the PHP docs site.

class ProductHelper {

    function sortProductsByPrice($products, $sort = SORT_ASC) {
        foreach ($products as $key => $row) {
            $name[$key]  = $row['name'];
            $rrp[$key] = $row['rrp'];
        }       
        array_multisort($rrp, $sort, $name, SORT_ASC, $products);
    }

    function sortProductsByName($products, $sort = SORT_ASC) {
        foreach ($products as $key => $row) {
            $name[$key] = $row['name'];
        }
        array_multisort($name, $sort, $products);
    }

}

This is how i’m using it:

        $products = $cur_prod_cat["products"]; // copy an array of products
        $PRODUCT_HELPER->sortProductsByName($products); //sort it

In case you need to see, the products array looks something like this:

Array (
    [0] => Array (
        [id] => 0
        [name] => product name
        [description] => product description
        [price] => product price
        [etc] => other attributes
    )
    [1] => Array (
        [id] => 1
        [name] => product name
        [description] => product description
        [price] => product price
        [etc] => other attributes
    )
)

Answer 1

You need to return $rrp in your first one and return $name in your second one, after your call to array_multisort.

This is because the function is sorting the variables $rrp and $name, instead of the ones you originally passed to the function.

Edit: If you’re simply trying to sort $products by it’s name array value, a better method entirely is the following:

function sort_name($a,$b) {
    return strcmp($a['name'],$b['name']);
}

$products = $cur_prod_cat["products"];
usort($products,'sort_name');

This uses the function sort_name to determine which element in the array to put first.

You can then create more sort_{value} functions if you desire, and just change the field value it contains.