PHP递归导航

Question

So i have this issue regarding recursive arrays. What i want is to get an recursive array with PHP from my database so that i can create a navigation menu with submenu's without creating another table.

this is the function i have so far;

function getMenu($tree = null){
        $tree2 = array();
        $tree = getPages();
        foreach($tree as $i => $item){
            if($item->parent_id == $item->ID){
                $tree2[$item->ID] = $item;
                $tree2[$item->ID]['submenu'] = getMenu($tree, $item->ID);
            }
        }

        return $tree2;
    }

To make things clear i did not create this function myself but got it from http://www.jugbit.com/php/php-recursive-menu-with-1-query/ and made adjustments where i thought where the right one

The $tree variable is coming from this function;

function getPages($limit = null,$sort = null) {
     global $db;
     $query = $db->prepare('SELECT * FROM pages ORDER BY Position');
     $query->execute();
     return $query->fetchAll(PDO::FETCH_CLASS);
}

Now i have been busting my balls over this for the last two days trying to figure out what i am doing wrong.

if i print the getMenu function all i get is an empty array wich i can't figure out why. it does get the foreach right and i don't think that's the issue but i'm not 100% sure..

i hope the question is clear but if it's not i'm sorry and will clarify where needed.

Thanks in advance

Answer 1

In getPages, if you want it to return an associative array, then you need to do:

return $query->fetchAll(PDO::FETCH_ASSOC);

and then your getMenu would look like:

function getMenu($tree = null, $parent = 0) {
    if (!isset($tree))
        $tree = getPages();

    $tree2 = array();
    foreach($tree as $i => $item) {
        if($item['id'] == $parent) {
            $tree2[$item['id']] = $item;
            $tree2[$item['id']]['submenu'] = getMenu($tree, $item['id']);
        }
    }

    return $tree2;
}