Promiseで処理が失敗したらリトライしたい Promiseの結果次第でリトライをかけたい場合があります。簡単な実装は以下で、これはググるとすぐに出てきます。 function retry(func, retryCount) { let promise = func(); for (let i = 1; i <= retryCount; ++i) { promise = promise.catch(func); } return promise; } // 失敗時に5回までリトライ retry(() => fetch("url"), 5).then(...) // これは以下と同じ fetch("url") .catch(() => fetch("url")) .catch(() => fetch("url")) .catch(() => fetch("url")) .catch(()
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