ant-design/components/form/demo/control-ref.tsx

import React from 'react';
import { Button, Form, Input, Select } from 'antd';
import type { FormInstance } from 'antd/es/form';

const { Option } = Select;

const layout = {
  labelCol: { span: 8 },
  wrapperCol: { span: 16 },
};

const tailLayout = {
  wrapperCol: { offset: 8, span: 16 },
};

const App: React.FC = () => {
  const formRef = React.useRef<FormInstance>(null);

  const onGenderChange = (value: string) => {
    switch (value) {
      case 'male':
        formRef.current?.setFieldsValue({ note: 'Hi, man!' });
        break;
      case 'female':
        formRef.current?.setFieldsValue({ note: 'Hi, lady!' });
        break;
      case 'other':
        formRef.current?.setFieldsValue({ note: 'Hi there!' });
        break;
      default:
        break;
    }
  };

  const onFinish = (values: any) => {
    console.log(values);
  };

  const onReset = () => {
    formRef.current?.resetFields();
  };

  const onFill = () => {
    formRef.current?.setFieldsValue({ note: 'Hello world!', gender: 'male' });
  };

  return (
    <Form
      {...layout}
      ref={formRef}
      name="control-ref"
      onFinish={onFinish}
      style={{ maxWidth: 600 }}
    >
      <Form.Item name="note" label="Note" rules={[{ required: true }]}>
        <Input />
      </Form.Item>
      <Form.Item name="gender" label="Gender" rules={[{ required: true }]}>
        <Select
          placeholder="Select a option and change input text above"
          onChange={onGenderChange}
          allowClear
        >
          <Option value="male">male</Option>
          <Option value="female">female</Option>
          <Option value="other">other</Option>
        </Select>
      </Form.Item>
      <Form.Item
        noStyle
        shouldUpdate={(prevValues, currentValues) => prevValues.gender !== currentValues.gender}
      >
        {({ getFieldValue }) =>
          getFieldValue('gender') === 'other' ? (
            <Form.Item name="customizeGender" label="Customize Gender" rules={[{ required: true }]}>
              <Input />
            </Form.Item>
          ) : null
        }
      </Form.Item>
      <Form.Item {...tailLayout}>
        <Button type="primary" htmlType="submit">
          Submit
        </Button>
        <Button htmlType="button" onClick={onReset}>
          Reset
        </Button>
        <Button type="link" htmlType="button" onClick={onFill}>
          Fill form
        </Button>
      </Form.Item>
    </Form>
  );
};

export default App;