ant-design/components/affix/demo/offset.md

order	title
1	zh-CN en-US 偏移 Offset

zh-CN

达到一定的偏移量才触发。

en-US

Affix element according to offset value.

import { Affix, Button } from 'antd';

ReactDOM.render(
  <Affix offsetTop={75}>
    <Button type="primary">75px to affix top</Button>
  </Affix>
, mountNode);