JavaScript 一些实用技巧

快速创建从0到n的数字

let arr1 = [...(new Array(n)).keys()];
let arr2 = Array.from({length:n},(v, k) => k);

Array.from 用法

Array.from({ length: 3 }, () => 'haha') // ["haha", "haha", "haha"]

随机返回几个 emoji

Array.from(
  {length: 7},
  (v, i) => String.fromCodePoint(
    129300 + Math.floor(Math.random() * 20)
  )
); 

// ["