Question

I have a large array.

In this array I have got (among many other things) a list of products:

$data['product_name_0'] = '';
$data['product_desc_0'] = '';
$data['product_name_1'] = '';
$data['product_desc_1'] = '';

This array is provided by a third party (so I have no control over this).

It is not known how many products there will be in the array.

What would be a clean way to loop though all the products?

I don’t want to use a foreach loop since it will also go through all the other items in the (large) array.

I cannot use a for loop cause I don’t know (yet) how many products the array contains.

I can do a while loop:

$i = 0;
while(true) { // doing this feels wrong, although it WILL end at some time (if there are no other products)
    if (!array_key_exists('product_name_'.$i, $data)) {
        break;
    }

    // do stuff with the current product

    $i++;
}

Is there a cleaner way of doing the above?

Doing a while(true) looks stupid to me or is there nothing wrong with this approach.

Or perhaps there is another approach?

Answer 1

Your method works, as long as the numeric portions are guaranteed to be sequential. If there’s gaps, it’ll miss anything that comes after the first gap.

You could use something like:

$names = preg_grep('/^product_name_\d+$/', array_keys($data));

which’ll return all of the ‘name’ keys from your array. You’d extract the digit portion from the key name, and then can use that to refer to the ‘desc’ section as well.

foreach($names as $name_field) {
   $id = substr($names, 12);
   $name_val = $data["product_name_{$id}"];
   $desc_val = $data["product_desc_{$id}"];
}