PHP method to get all subcategories under a category_PHP tutorial

    static function getMenuTree($arrCat, $parent_id = 0, $level = 0,$all=True)
    {
        static  $arrTree; //使用static代替global
        if(!$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[$key]); //注销当前节点数据，减少已无用的遍历
                self::getMenuTree($arrCat, $value[ 'cid'], $level);
            }
        }
        return $arrTree;
    }

	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'=>$val['parent_cid'],'root_cid'=>$val['root_cid']);
        }

        $applist = "<?php\nreturn ".var_export($arr, true).";\n?>";
        file_put_contents($filepath.&#39;itemcat.php&#39;, $applist);
    }