public function getParentCates($cateId){
$model = M('download_cate');
$parentId = $model->where(['id'=>$cateId])->getField('parent_id') ? : 0;
$data = $model->where(['parent_id'=>$parentId])->select();
$res[] = ['selid'=>$cateId,'data'=>$data];
if($parentId > 0){
$res = array_merge($this->getParentCates($parentId));
}
return $res;
}