30秒学会 JavaScript 片段 – Random element in array

Gets a random element from an array.

• Use Math.random() to generate a random number.
• Multiply it by Array.prototype.length and round it off to the nearest whole number using Math.floor().
• This method also works with strings.

代码实现

const sample = arr => arr[Math.floor(Math.random() * arr.length)];

sample([3, 7, 9, 11]); // 9

翻译自：https://www.30secondsofcode.org/js/s/array-sample