PHP:将线性数组转换为树形结构数组

function buildTree($array, $parentId = 0) {
    $tree = array();
    foreach ($array as $item) {
        if ($item['parent_id'] == $parentId) {
            $children = buildTree($array, $item['id']);
            if ($children) {
                $item['children'] = $children;
            }
            $tree[] = $item;
        }
    }
    return $tree;
}

// 示例数据
$data = array(
    array('id' => 1, 'name' => '节点1', 'parent_id' => 0),
    array('id' => 2, 'name' => '节点2', 'parent_id' => 0),
    array('id' => 3, 'name' => '节点1.1', 'parent_id' => 1),
    array('id' => 4, 'name' => '节点1.2', 'parent_id' => 1),
    array('id' => 5, 'name' => '节点2.1', 'parent_id' => 2),
    array('id' => 6, 'name' => '节点2.2', 'parent_id' => 2),
    array('id' => 7, 'name' => '节点1.1.1', 'parent_id' => 3),
);

$tree = buildTree($data);
print_r($tree);