数组、对象拷贝

0x01 ...

浅拷贝，只能拷贝最外面一层

example

good	bad
let orgin = [1, null, 3, undefined, 5]; let clone = [...orgin]; clone[2] = "changed";	const orgin = [ 1, { code: "source", value: 1 }, { code: "source", value: 2 }, { code: "source", value: 3 }, { code: "source", value: 4 } ]; let clone = [...orgin]; clone[2].value = "changed"; console.log(orgin[2].value); // "changed"

0x02 JSON.parse(JSON.stringify)

json 转为字符串再格式化为 json

good	bad
const orgin = [ 1, { code: "source", value: 1 }, { code: "source", value: 2 }, { code: "source", value: 3 }, { code: "source", value: 4 } ]; let clone = JSON.parse(JSON.stringify(orgin));	const orgin = [ 1, { code: "source", value: 1 }, { code: "source", value: 2 }, { code: "source", value: undefined }, { code: "source", value: 4 } ]; let clone = JSON.parse(JSON.stringify(orgin)); console.log(clone[3]); // {code:"source"}

0x03 Notification()

只在浏览器中适用

https://developer.mozilla.org/zh-CN/docs/Web/API/notification

function structuralClone(obj) {
  return new Notification("", { data: obj, silent: true }).data;
}

let clone = structuralClone(orgin);

Ref

https://justjavac.com/javascript/2018/02/02/deep-copy.html

https://dassur.ma/things/deep-copy/