var arr = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]; for (var i=0,len=arr.length; i<len; ++i) { var value = arr[i]; if (value > 5) { break; } console.log(value); } [runstant] Array.prototype.some 5 より大きかったら true を返す. するとそれ以降のループが止まるので forEach っぽく書けてかつ break っぽいことができます. var arr = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]; arr.some(function(value) { if (value > 5) { return true; } console.log(value); });
![[JavaScript] ループ途中で抜ける処理は for(in break) ではなく some を使おう♪ - Qiita](https://cdn-ak-scissors.b.st-hatena.com/image/square/79e86d9834c3b8962d2b080a44fb69c9522202c0/height=288;version=1;width=512/https%3A%2F%2Fqiita-user-contents.imgix.net%2Fhttps%253A%252F%252Fcdn.qiita.com%252Fassets%252Fpublic%252Farticle-ogp-background-9f5428127621718a910c8b63951390ad.png%3Fixlib%3Drb-4.0.0%26w%3D1200%26mark64%3DaHR0cHM6Ly9xaWl0YS11c2VyLWNvbnRlbnRzLmltZ2l4Lm5ldC9-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%26mark-x%3D142%26mark-y%3D112%26blend64%3DaHR0cHM6Ly9xaWl0YS11c2VyLWNvbnRlbnRzLmltZ2l4Lm5ldC9-dGV4dD9peGxpYj1yYi00LjAuMCZ3PTYxNiZ0eHQ9JTQwcGhpJnR4dC1jb2xvcj0lMjMyMTIxMjEmdHh0LWZvbnQ9SGlyYWdpbm8lMjBTYW5zJTIwVzYmdHh0LXNpemU9MzYmdHh0LWFsaWduPWxlZnQlMkN0b3Amcz1hNzMyODE2YjRmOTNiOTE5N2U1YjI1NGNlZGNmMGY1OA%26blend-x%3D142%26blend-y%3D491%26blend-mode%3Dnormal%26s%3D199f26470375c52d111a087603c8e0f1)