$layer=1; //用来跟踪当前菜单的级数
$sql="select * from channels where parentid=0";
$root=$this->db->query($sql);
if($root->num_rows()>0) {
$this->load->model('Showtreemenu');
$data['station']=$this->Showtreemenu->showbyselect($root,$layer);
$this->load->view('adminweblogin/adv_info_add',$data);
}