ant-design/components/input-number/demo/addon.tsx

import React from 'react';
import { SettingOutlined } from '@ant-design/icons';
import { Cascader, InputNumber, Select, Space } from 'antd';

const { Option } = Select;

const selectBefore = (
  <Select defaultValue="add" style={{ width: 60 }}>
    <Option value="add">+</Option>
    <Option value="minus">-</Option>
  </Select>
);
const selectAfter = (
  <Select defaultValue="USD" style={{ width: 60 }}>
    <Option value="USD">$</Option>
    <Option value="EUR">€</Option>
    <Option value="GBP">£</Option>
    <Option value="CNY">¥</Option>
  </Select>
);

const App: React.FC = () => (
  <Space direction="vertical">
    <InputNumber addonBefore="+" addonAfter="$" defaultValue={100} />
    <InputNumber addonBefore={selectBefore} addonAfter={selectAfter} defaultValue={100} />
    <InputNumber addonAfter={<SettingOutlined />} defaultValue={100} />
    <InputNumber
      addonBefore={<Cascader placeholder="cascader" style={{ width: 150 }} />}
      defaultValue={100}
    />
  </Space>
);

export default App;