業界トップクラスの求人数を誇る転職エージェントPR

リクルートグループのコネクションを活かした非公開求人も充実、他にはない好条件の求人と出会える

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二次元配列を一次元配列にする

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たとえば、[[1,2,3],[5, 6, 7]] という二次元配列があったとして、これを [1, 2, 3, 4, 5, 6, 7] というふうにひとつの配列にまとめたい場合、Array.reduce を使えば簡潔に書くことができる。

const arrayOfArray = [[1,2,3],[5, 6, 7]];
const flattenedArray = arrayOfArray.reduce((acc, eachArray) => acc.concat(eachArray), []);
console.log(flattenedArray); //[1, 2, 3, 4, 5, 6, 7]

MDN Array.reduce

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