katayama8000

<p>useEffect の依存配列は、<br>
「変更があることに実行」ではなく<br>
「再レンダーごとに実行、ただし変更がなければスキップ」。</p>
<p>なので依存配列を渡さなかった場合には再レンダーごとに実行される。</p>


<p><span class="embed-block zenn-embedded zenn-embedded-card"><iframe id="zenn-embedded__b4d32862ed791" src="https://embed.zenn.studio/card#zenn-embedded__b4d32862ed791" data-content="https%3A%2F%2Fqiita.com%2Fk-penguin-sato%2Fitems%2F9373d87c57da3b74a9e6" frameborder="0" scrolling="no" loading="lazy"></iframe></span><a href="https://qiita.com/k-penguin-sato/items/9373d87c57da3b74a9e6" style="display:none" target="_blank" rel="nofollow noopener noreferrer">https://qiita.com/k-penguin-sato/items/9373d87c57da3b74a9e6</a></p>
<p>useEffectの代に引数が空だと、毎回実行される</p>


<p><a href="https://www.youtube.com/watch?v=GGo3MVBFr1A" target="_blank" rel="nofollow noopener noreferrer">youtube_link</a></p>
<p>初学者がやりがちなミス</p>


<p><span class="embed-block zenn-embedded zenn-embedded-card"><iframe id="zenn-embedded__649508c7ee9d" src="https://embed.zenn.studio/card#zenn-embedded__649508c7ee9d" data-content="https%3A%2F%2Fzenn.dev%2Fhiromu617%2Farticles%2F88088a37900ab5" frameborder="0" scrolling="no" loading="lazy"></iframe></span><a href="https://zenn.dev/hiromu617/articles/88088a37900ab5" style="display:none" target="_blank">https://zenn.dev/hiromu617/articles/88088a37900ab5</a></p>


<p><span class="embed-block zenn-embedded zenn-embedded-card"><iframe id="zenn-embedded__80309301acb64" src="https://embed.zenn.studio/card#zenn-embedded__80309301acb64" data-content="https%3A%2F%2Fbeta.reactjs.org%2F" frameborder="0" scrolling="no" loading="lazy"></iframe></span><a href="https://beta.reactjs.org/" style="display:none" target="_blank" rel="nofollow noopener noreferrer">https://beta.reactjs.org/</a></p>
