feat: allow string type z-index

src/index-bar/README.md

@@ -65,7 +65,7 @@ export default {
 | Attribute | Description | Type | Default |
 |------|------|------|------|
 | index-list | Index List | *string[] \| number[]* | `A-Z` |
-| z-index | z-index | *number* | `1` |
+| z-index | z-index | *string \| number* | `1` |
 | sticky | Whether to enable anchor sticky top | *boolean* | `true` |
 | sticky-offset-top `v2.0.7` | Anchor offset top when sticky | *number* | `0` |
 | highlight-color | Index character highlight color | *string* | `#07c160` | - |

src/index-bar/README.zh-CN.md

@@ -69,7 +69,7 @@ export default {
 | 参数 | 说明 | 类型 | 默认值 |
 |------|------|------|------|
 | index-list | 索引字符列表 | *string[] \| number[]* | `A-Z` |
-| z-index | z-index 层级 | *number* | `1` |
+| z-index | z-index 层级 | *string \| number* | `1` |
 | sticky | 是否开启锚点自动吸顶 | *boolean* | `true` |
 | sticky-offset-top `v2.0.7` | 锚点自动吸顶时与顶部的距离 | *number* | `0` |
 | highlight-color | 索引字符高亮颜色 | *string* | `#07c160` |

src/index-bar/index.js

@@ -42,7 +42,7 @@ export default createComponent({
   ],
 
   props: {
-    zIndex: Number,
+    zIndex: [Number, String],
     highlightColor: String,
     sticky: {
       type: Boolean,