编写 ES6 的 7 个实用技巧

Hack #1 — 变量交换

使用数组解构交换变量的值

let a = 'world', b = 'hello'
[a, b] = [b, a]
console.log(a) // -> hello
console.log(b) // -> world

// Yes, it's magic

Hack #2 — 解构 Async/Await

再强调一遍,数组解构非常好用。结合 async/awaitpromises能让复杂的流程变得简单。

const [user, account] = await Promise.all([
  fetch('/user'),
  fetch('/account')
])

Hack #3 — 调试

对于任何喜欢用console.log进行调试的人来说,这都是一个好方法(当然,用console.table也可以):

const a = 5, b = 6, c = 7
console.log({ a, b, c })

// outputs this nice object:
// {
//    a: 5,
//    b: 6,
//    c: 7
// }

Hack #4 — 一行代码

操作数组时,这会让代码结构变得更为紧凑

// Find max value
const max = (arr) => Math.max(...arr);
max([123, 321, 32]) // outputs: 321

// Sum array
const sum = (arr) => arr.reduce((a, b) => (a + b), 0)
sum([1, 2, 3, 4]) // output: 10

Hack #5 — 连接数组

使用展开运算符...代替 concat:

const one = ['a', 'b', 'c']
const two = ['d', 'e', 'f']
const three = ['g', 'h', 'i']

// Old way #1
const result = one.concat(two, three)

// Old way #2
const result = [].concat(one, two, three)

// New
const result = [...one, ...two, ...three]

Hack #6 — 复制

下面的方法用于复制(浅复制)数组/对象:

const obj = { ...oldObj }
const arr = [ ...oldArr ]

Hack #7 —命名参数

解构命名参数,提升函数声明和函数调用的可读性:

const getStuffNotBad = (id, force, verbose) => {
  ...do stuff
}
const getStuffAwesome = ({ id, name, force, verbose }) => {
  ...do stuff
}

// Somewhere else in the codebase... WTF is true, true?
getStuffNotBad(150, true, true)

// Somewhere else in the codebase... I ❤ JS!!!
getStuffAwesome({ id: 150, force: true, verbose: true })

阅读原文:https://medium.com/dailyjs/7-hacks-for-es6-developers-4e24ff425d0b

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转载自www.cnblogs.com/fayin/p/9098856.html