php的无限分类操作

/**
 * @Description: 无限极分类一
 * @Author: Yang
 * @param $data  数据库数据
 * @param int $parent_id   父级ID
 * @return array
 */
function getTree1($data, $parent_id = 0)
{
    $tree = array();
    foreach ($data as $k => $v) {
        if ($v["parent_id"] == $parent_id) {
            unset($data[$k]);
            if (!empty($data)) {
                $children = getTree1($data, $v["id"]);
                if (!empty($children)) {
                    $v["_child"] = $children;
                }
            }
            $tree[] = $v;
        }
    }
    return $tree;
}


/**
 * @Description: 无限极分类二
 * @Author: Yang
 * @param $data   数据库数据
 * @param int $parent_id  父级ID
 * @param int $level  等级
 * @return array
 */
function getTree2($data, $parent_id = 0, $level = 0)
{
    static $tree = array();
    foreach ($data as $k => $v) {
        if ($v["parent_id"] == $parent_id) {
            $v["level"] = $level;
            $tree[] = $v;
            getTree2($data, $v["id"], $level + 1);
        }
    }
    return $tree;
}

/**
 * @Description: 无限分类三：面包屑导航
 * @Author: Yang
 * @param $data  数据库数据
 * @param $id    分类ID
 * @return array
 */
function getCrumbsBar($data, $id) {
    static $tree = array();
    foreach ($data as $k => $v) {
        if ($v["id"] == $id) {
            getCrumbsBar($data, $v["parent_id"]);
            $tree[] = $v;
        }
    }
    return $tree;
}