const twoDimensionsObjArray = [ { key: 1, value: 'aaa', array: [ { aryKey: 10, aryVal: 'a' }, { aryKey: 20, aryVal: 'b' } ] }, { key: 2, value: 'bbb', array: [ { aryKey: 30, aryVal: 'c' }, { aryKey: 40, aryVal: 'd' } ] } ] twoDimensionsObj…

flat() const twoDimensionsArray = [[1a, 1b, 1c], [2a, 2b, 2c], [3a, 3b, 3c]] twoDimensionsArray.flat() => ['1a', '1b', '1c', '2a', '2b', '2c', '3a', '3b', '3c'] flatMap() flatMap()を使うと、 オブジェクトの配列内にある配列の平坦な連想配列を…