kei_s_lifehack https://blog.hatena.ne.jp/kei_s_lifehack/ KAEDE Hack blog https://kei-s-lifehack.hatenablog.com/ React useState使い方 なぜ使うか A: Class, super, this... と書くより短くかけるから code www.udemy.com これを参考にした まずcreate-react-app で作ったprojectに import React, { useState } from 'react'; で, {useState }を追加 アローfnで入れ物を書く． const App = props => { ....... return ( <div> </div> ) } ここに stateの初期化 switch関数などの関数 personsを表示するreturn (… 190 <iframe src="https://hatenablog-parts.com/embed?url=https%3A%2F%2Fkei-s-lifehack.hatenablog.com%2Fentry%2F2020%2F05%2F28%2FReact-useState" title="React useState useEffect使い方 - KAEDE Hack blog" class="embed-card embed-blogcard" scrolling="no" frameborder="0" style="display: block; width: 100%; height: 190px; max-width: 500px; margin: 10px 0px;"></iframe> https://cdn-ak.f.st-hatena.com/images/fotolife/k/kei_s_lifehack/20200528/20200528055336.png Hatena Blog https://hatena.blog 2020-05-28 06:02:23 rich https://kei-s-lifehack.hatenablog.com/entry/2020/05/28/React-useState 1.0 100%