(실습) 시계 만들기

실제 실습 내용

- create-react로 만든 my-app 프로젝트를 열어 chapter_04 폴더 생성

 

- Clock.jsx 코드 작성 

import React from "react";

function Clock(props){
    return (
        <div>
            <h1>안녕, 리액트!</h1>
            <h2>현재 시간 : {new Date().toLocaleTimeString()}</h2>
        </div>
    );
}

export default Clock;

 

- index.js 코드 변경 

import React from 'react';
import ReactDOM from 'react-dom/client';
import './index.css';
import App from './App';
import reportWebVitals from './reportWebVitals';

import Library from './chapter_03/Library';
import Clock from './chapter_04/Clock';
import CommentList from './chapter_05/CommentList';


setInterval(() => {
  const root = ReactDOM.createRoot(document.getElementById('root'));
root.render(
  <React.StrictMode>
    <Clock />
  </React.StrictMode>,
  document.getElementById('root')
);
}, 1000);

// If you want to start measuring performance in your app, pass a function
// to log results (for example: reportWebVitals(console.log))
// or send to an analytics endpoint. Learn more: https://bit.ly/CRA-vitals
reportWebVitals();

 

실행 결과