feat(DropdownMenu): duration can be string

src/dropdown-menu/README.md

@@ -113,9 +113,9 @@ Use `active-color` prop to custom active color of the title and options
 | Attribute | Description | Type | Default |
 |------|------|------|------|
 | active-color | Active color of title and option | *string* | `#1989fa` |
-| z-index | z-index of menu item | *number \| string* | `10` |
-| duration | Transition duration, unit second | *number* | `0.2` |
 | direction `v2.0.1` | Expand direction, can be set to `up` | *string* | `down` |
+| z-index | z-index of menu item | *number \| string* | `10` |
+| duration | Transition duration, unit second | *number \| string* | `0.2` |
 | overlay | Whether to show overlay | *boolean* | `true` |
 | close-on-click-overlay | Whether to close when click overlay | *boolean* | `true` |
 | close-on-click-outside `v2.0.7` | Whether to close when click outside | *boolean* | `true` |

src/dropdown-menu/README.zh-CN.md

@@ -117,9 +117,9 @@ export default {
 | 参数 | 说明 | 类型 | 默认值 |
 |------|------|------|------|
 | active-color | 菜单标题和选项的选中态颜色 | *string* | `#1989fa` |
-| z-index | 菜单栏 z-index 层级 | *number \| string* | `10` |
-| duration | 动画时长，单位秒 | *number* | `0.2` |
 | direction `v2.0.1` | 菜单展开方向，可选值为`up` | *string* | `down` |
+| z-index | 菜单栏 z-index 层级 | *number \| string* | `10` |
+| duration | 动画时长，单位秒 | *number \| string* | `0.2` |
 | overlay | 是否显示遮罩层 | *boolean* | `true` |
 | close-on-click-overlay | 是否在点击遮罩层后关闭菜单 | *boolean* | `true` |
 | close-on-click-outside `v2.0.7` | 是否在点击外部元素后关闭菜单 | *boolean* | `true` |

src/dropdown-menu/index.js

@@ -26,7 +26,7 @@ export default createComponent({
       default: true,
     },
     duration: {
-      type: Number,
+      type: [Number, String],
       default: 0.2,
     },
     direction: {