tako_eng https://blog.hatena.ne.jp/tako_eng/ blog https://tako-eng.hatenablog.com/ プログラミング(JavaScript) trueになるから、条件式自体をreturnすればOK 変更前 'use strict'; { const numbers = [1, 4, 7, 8, 10]; const evenNumbers = numbers.filter(number =>{ if(number % 2 === 0){ return true; }else{ return false; } }); console.log(evenNumbers); } // 実行結果 [ 4, 8, 10 ] 変更後 { const numbers = [1, 4, 7, 8, 10]; const evenNumbers = n… 190 <iframe src="https://hatenablog-parts.com/embed?url=https%3A%2F%2Ftako-eng.hatenablog.com%2Fentry%2F2020%2F04%2F08%2F070000" title="JavaScript 短く書いてみるメモ - blog" class="embed-card embed-blogcard" scrolling="no" frameborder="0" style="display: block; width: 100%; height: 190px; max-width: 500px; margin: 10px 0px;"></iframe> Hatena Blog https://hatena.blog 2020-04-08 07:00:00 rich https://tako-eng.hatenablog.com/entry/2020/04/08/070000 1.0 100%