完善功能

app/admin/service/goods/GoodsService.php

@@ -296,7 +296,7 @@ class GoodsService
         try {
             $model = new Goods();
             $model->goods_id = $params['goods_id'];
-            $model->join_goods_category_id = $params['join_goods_category_id'] ?? '';
+            $model->join_goods_category_id = $params['join_goods_category_id'] ?? 0;
             $model->goods_classify = $params['goods_classify'] ?? '';
             $model->goods_status = $params['goods_status'] ?? '';
             $model->goods_category = $params['goods_category'] ?? '';