function makeTree()
        {
            $areas = $this->arr();
            $areaTree = [];
            foreach ($areas as $id=>$area)
            {
                if(isset($areas[$area["pid"]]))
                {
                    $areas[$area["pid"]]["children"][] = &$areas[$id];
                } 
                else 
                {
......................

$add_cond['open_id'] = 'odnyQ5_lyKmYCcWirvxcQxdkRx4I';//$this->userinfo['openid'];
        $add_cond['spot_open_id'] = 'odnyQ54EwmeGasMU8cAVyCHkTBw8';//$_POST['spot_open_id'];
        $spot = M('activity_like')
        ->where(['spot_open_id'=>$add_cond['spot_open_id'],'open_id'=>$add_cond['open_id']])
        ->find();
        if ($spot) 
        {
          $this->ajaxReturn(['status'=>0,'info'=>'已点赞，请不要重复']);
        }
$add_cond['like_status'] = 1;
$add_liked = M('activity_like')->add($add_cond);
if ($add_liked) 
......................