录入食物关联营养素时，选择营养素后，单位自动更新为营养素的默认单位

src/views/food/nutrient.vue

@@ -13,6 +13,7 @@
         placeholder="请输入营养素关键词"
         :remote-method="queryNutrients"
         :loading="loading"
+        @change="nutrientChanged"
       >
         <el-option v-for="item in nutrients" :key="item.id" :label="item.name" :value="item.id" />
       </el-select>
@@ -365,6 +366,14 @@ export default {
       this.$set(row, 'quantityMin', '')
       this.$set(row, 'quantityMax', '')
       this.$set(row, 'quantity', '')
+    },
+    nutrientChanged(value) {
+      for (let nutrient of this.nutrients) {
+        if (nutrient.id === value) {
+          this.$set(this.params, 'unit', nutrient.baseUnit)
+          break
+        }
+      }
     }
   }
 }