“Como podemos definir o React Selecionar necessário” Respostas de código

Como podemos definir o React Selecionar necessário

import React from "react";
import { Form, Select, Button } from "antd";
import "./styles.css";
import "antd/dist/antd.css";
const { Option } = Select;

const AppWithForm = props => {
  const { getFieldDecorator } = props.form;

  const handleSubmit = () => {
    props.form.validateFields((err, values) => {
      if (!err) {
        console.log("Received values of form: ", values);
      } else console.log("form is NOT valid");
    });
  };

  const onChange = value => {
    console.log(`selected ${value}`);
  };

  return (
    <div className="App">
      <Form layout="inline">
        <Form.Item>
          {getFieldDecorator("dropdown", {
            rules: [{ required: true, message: "Please select a person!" }]
          })(
            <Select
              showSearch={false}
              style={{ width: 200 }}
              placeholder="Select a person"
              optionFilterProp="children"
              onChange={onChange}
            >
              <Option value="jack">Jack</Option>
              <Option value="lucy">Lucy</Option>
              <Option value="tom">Tom</Option>
            </Select>
          )}
        </Form.Item>
        <Form.Item>
          <Button type="primary" onClick={handleSubmit}>
            Save
          </Button>
        </Form.Item>
      </Form>
    </div>
  );
};

const App = Form.create({})(AppWithForm);

export default App;