修改购物车递减接口

@@ -237,6 +237,8 @@ class Car extends Api
         if (empty($car_id)) $this->error('缺少参数 car_id!');
         $where['user_id'] = $userId;
         $where['id'] = $car_id;
+        $carInfo = $this->carModel->where('id',$car_id)->find();
+        if ($carInfo['number'] == 1) $this->error('不可以再减了');
 
         $res = $this->carModel->where($where)->setDec('number',1);
         if ($res) $this->success('SUCCESS');