How to recursively build a <select> with unknown tree depth

Question

I have a MySQL table with a tree data structure. The fields are _id, name and parentId. When the record hasn\'t a parent, parent

Answer 1

Your problem is already solved within the SPL. The RecursiveIteratorIteratorDocs has the information about one's item's depth:

$it = new RecursiveIteratorIterator(new RecursiveArrayIterator($array), SELF_FIRST);
foreach ($it as $key => $element)
{
    if ($key !== 'name') continue;
    $inset = str_repeat('--', $it->getDepth());
    printf('%s %s', $inset, $element);
}