标签：面试题 cacheMap temp js cloneDeep key obj 拷贝 const
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>深拷贝</title>
</head>
<body>
<script>
const obj1 = {
array: [1, 2],
arrayOfObj: [{ a: 3 }, { b: 4 }],
obj: { c: 5 },
reg: /7/,
data: new Date(),
map: new Map([['d', 8], ['e', 9]]),
set: new Set([10, 11]),
num: 12,
str: 'xxx',
bol: false,
fn: function () { console.log(13) },
nulVal: null,
undVal: undefined
}
function cloneDeep (obj = {}, cacheMap = new WeakMap()) {
if (typeof obj !== "object" || !obj) {
return obj
}
if (cacheMap.has(obj)) {
return cacheMap.get(obj)
}
let temp, params;
const constructor = obj.constructor;
if (obj instanceof RegExp || obj instanceof Date) {
params = obj
}
temp = new constructor(params)
cacheMap.set(obj, temp)
if (obj instanceof Map) {
for (const [key, value] of obj) {
temp.set(cloneDeep(key, cacheMap), cloneDeep(value, cacheMap))
}
} else if (obj instanceof Set) {
for (const value of obj) {
temp.add(cloneDeep(value, cacheMap))
}
} else {
for (let key in obj) {
if (obj.hasOwnProperty(key)) {
temp[key] = cloneDeep(obj[key], cacheMap)
}
}
}
return temp;
}
const obj2 = {
to: obj1
}
obj1.to = obj2
const result = cloneDeep(obj1)
console.log(obj1, result);
</script>
</body>
</html>
标签：面试题,
cacheMap,
temp,
js,
cloneDeep,
key,
obj,
拷贝,
const
From： https://www.cnblogs.com/iooz/p/17113909.html