PHP gets all the subclass methods below the classification

Get all the subclass methods below the taxonomy:

    static function Getmenutree ($arrCat, $parent _id = 0, $level = 0, $all =true)    {        static  $arrTree;// Use static instead of global        if (! $all) $arrTree = ';        if (empty ($arrCat)) return FALSE;        $level + +;        if ($level = = 1) $arrTree [] = $parent _id;        foreach ($arrCat as $key = + $value)        {            if ($value [' parent_cid '] = = $parent _id)            {                //$value [' Level ' ] = $level;                $arrTree [] = $value [' CID '];                Unset ($arrCat [$key]); Unregisters the current node data, reducing the useless traversal                self::getmenutree ($arrCat, $value [' CID '], $level);            }        }        return $arrTree;    }

The premise of using this method is to write the classification to the cache file, the cache file is written as follows:

Public Function ActionIndex2 () {        $filepath = Yii::getpathofalias (' application '). ' /data/';        $arr = Array ();        $db = Yii::app ()->db;        $listinfo = $db->createcommand ("Select Name,cid,parent_cid,root_cid from Item_cat_info")->queryall ();        foreach ($listinfo as $val)        {            $arr [$val [' cid ']] = Array (' cid ' + = $val [' CID '], ' name ' = + $val [' name '], ' Parent_cid ' = ' $val [' parent_cid '], ' root_cid ' and ' = ' $val [' root_cid ']);        }        $applist = "<?php\nreturn". Var_export ($arr, true). "; N?> ";        File_put_contents ($filepath. ' itemcat.php ', $applist);    }