Online PHP editor | refs for 6vRYe

<?php $strings = [ "cat:others;id:4,9,13", "id:4,9,13;cat:electric-products", "id:4,9,13;cat:foods", "cat:drinks,foods" ]; $result = ['id' => [], 'cat' => []]; foreach ($strings as $string) { foreach (explode(';', $string) as $segment) { [$key, $values] = explode(':', $segment, 2); array_push($result[$key], ...explode(',', $values)); } } var_export(array_unique($result['id'])); echo "\n---\n"; var_export(array_unique($result['cat']));