更新

@@ -128,7 +128,7 @@ class Buy extends Api
 
         $model = new \app\api\model\UserBuylist();
         $order = $model->with('sku')->where('id',$id)->find();
-        if ($number+$order['number'] > $order['stock_num']) $this->error('已达到最大库存，请勿重复提交');
+        if ($number+$order['number'] > $order['sku']['stock_num']) $this->error('已达到最大库存，请勿重复提交');
         $model->where('id',$id)->setInc('number',$number);
         $this->success('SUCCESS');
     }

@@ -97,7 +97,7 @@ class Cart extends Api
 
         $model = new \app\api\model\Cart();
         $order = $model->with('sku')->where('id',$id)->find();
-        if ($number+$order['number'] > $order['stock_num']) $this->error('已达到最大库存，请勿重复提交');
+        if ($number+$order['number'] > $order['sku']['stock_num']) $this->error('已达到最大库存，请勿重复提交');
         $model->where('id',$id)->setInc('number',$number);
         $this->success('SUCCESS');
     }