Add commas to items and with "and" near the end in PHP

Question

I want to add a comma to every item except the last one. The last one must have "and".

Item 1, Item 2 and Item 3

But items can be from 1 +

So if one item:

Item 1

If two items:

Item 1 and Item 2

If three items:

Item 1, Item 2 and Item 3

If four items:

Item 1, Item 2, Item 3 and Item 4

etc, etc.

Answer 1

Here's a variant that has an option to support the controversial Oxford Comma and takes a parameter for the conjunction (and/or). Note the extra check for two items; not even Oxford supporters use a comma in this case.

function conjoinList($items, $conjunction='and', $oxford=false) {
    $count = count($items);

    if ($count === 0){
        return '';
    } elseif ($count === 1){
        return $items[0];
    } elseif ($oxford && ($count === 2)){
        $oxford = false;
    }

    return implode(', ', array_slice($items, 0, -1)) . ($oxford? ', ': ' ') . $conjunction . ' ' . end($items);
}