thinkphp5中使用无极限分类

1. 先根据普通递归完成无限极分类 

2. 再根据分号的类的level 添加字符，再次存入数组的_name字段，最后按照_name字段输出

/**
     * 获得树状数据
     * @param $data 数据
     * @param $title               数据库中字段名
     * @param string $fieldPri     数据库中主键id
     * @param string $fieldPid     数据库中父id
     * @return array
     */
    static public function tree($data, $title, $fieldPri = 'cid', $fieldPid = 'pid')
    {
        if (!is_array($data) || empty($data))
            return array();
        $arr = Data::channelList($data);
        foreach ($arr as $k => $v) {
            $str = "";
            if ($v['_level'] > 2) {
                for ($i = 1; $i < $v['_level'] - 1; $i++) {
                    $str .= "│    ";
                }
            }
            if ($v['_level'] != 1) {
                $t = $title ? $v[$title] : "";
                if (isset($arr[$k + 1]) && $arr[$k + 1]['_level'] >= $arr[$k]['_level']) {
                    $arr[$k]['_name'] = $str . "├─ " . $v['_html'] . $t;
                } else {
                    $arr[$k]['_name'] = $str . "└─ " . $v['_html'] . $t;
                }
            } else {
                $arr[$k]['_name'] = $v[$title];
            }
        }
        //设置主键为$fieldPri
        $data = array();
        foreach ($arr as $d) {
            $data[$d[$fieldPri]] = $d;
        }
        return $data;
    }

 /**
     * 获得所有子栏目
     * @param $data 栏目数据
     * @param int $pid 操作的栏目
     * @param string $html 栏目名前字符
     * @param string $fieldPri 表主键
     * @param string $fieldPid 父id
     * @param int $level 等级
     * @return array
     */
    static public function channelList($data, $pid = 0, $html = " ", $fieldPri = 'cid', $fieldPid = 'pid', $level = 1)
    {
        $data = self::_channelList($data, $pid, $html, $fieldPri, $fieldPid, $level);
        if (empty($data))
            return $data;

        foreach ($data as $n => $m) {
            if ($m['_level'] == 1)
                continue;//结束单次循环
            $data[$n]['_first'] = false;
            $data[$n]['_end'] = false;
            if (!isset($data[$n - 1]) || $data[$n - 1]['_level'] != $m['_level']) {
                $data[$n]['_first'] = true; 
            }
            if (isset($data[$n + 1]) && $data[$n]['_level'] > $data[$n + 1]['_level']) {
                $data[$n]['_end'] = true;
            }
        }
        //更新key为栏目主键
        $category=array();
        foreach($data as $d){
            $category[$d[$fieldPri]]=$d;
        }
        return $category;
    }

//只供channelList方法使用

    /**
     * 获得所有子栏目
     * @param $data  栏目数据
     * @param int $pid 操作的栏目
     * @param string $html 栏目名前字符
     * @param string $fieldPri 表主键
     * @param string $fieldPid 父id
     * @param int $level 等级
     * @return array
     */
    static private function _channelList($data, $pid = 0, $html = " ", $fieldPri = 'cid', $fieldPid = 'pid', $level = 1)
    {
        if (empty($data))
            return array();
        $arr = array();

        foreach ($data as $v) {
            $id = $v[$fieldPri];
            if ($v[$fieldPid] == $pid) {
                $v['_level'] = $level;
                $v['_html'] = str_repeat($html, $level - 1);
                $arr[] = $v;

                $tmp = self::_channelList($data, $id, $html, $fieldPri, $fieldPid, $level + 1);
                $arr = array_merge($arr, $tmp);//array_merge把两个数组整合为一个数组
            }
        }
        return $arr;
    }