参考 目的 プロジェクトで使用されている不適切なuseEffectを減らす 本題 Reactの公式ドキュメントにuseEffectは必要ないかもしれない,というようなページがありとても勉強になったので記事にしようと思いました. データフェッチング アプリのデータフェッチングをuseEffect内で行うのはよく知られている方法です. Bad 💣 function SearchResults({ query }) { const [results, setResults] = useState([]); const [page, setPage] = useState(1); useEffect(() => { // 🔴 Avoid: クリーンアップなしでのフェッチング fetchResults(query, page).then(json => { setResults(json); }
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