> For the complete documentation index, see [llms.txt](https://ddzy.gitbook.io/ts-utility-plugins-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://ddzy.gitbook.io/ts-utility-plugins-docs/utility/utility-others/isundefined.md).

# isUndefined

### 说明

 判断是否为严格的`undefined`

### 源码

<https://github.com/ddzy/ts-utility-plugins/tree/master/src/ddzy/utility/others/isUndefined>

### 用法

{% code title="isUndefined.test.ts" %}

```typescript
*
```

{% endcode %}