laravel8 实现递归处理 与无限级分类

1.无限级分类 

    /*** 数组的合并，并加上html标识前缀* @param array $data* @param int $pid* @param string $html* @param int $level* @return array*/public function treeLevel(array $data, int $pid = 0, string $html = '--', int $level = 0) {static $arr = [];foreach ($data as $val) {if ($pid == $val['pid']) {// 重复一个字符多少次$val['html'] = str_repeat($html, $level * 2);$val['level'] = $level + 1;$arr[] = $val;$this->treeLevel($data, $val['id'], $html, $val['level']);}}return $arr;}

2.递归

    /*** 数据多层级* @param array $data* @param int $pid* @return array*/public function subTree(array $data, int $pid = 0) {// 返回的结果$arr = [];foreach ($data as $val) {// 给定的PID是当前记录的上级IDif ($pid == $val['pid']) {// 递归$val['sub'] = $this->subTree($data,$val['id']);$arr[] = $val;}}return $arr;}