cloneDeep 深克隆实现

Copy 
1var obj = {
2  //原数据，包含字符串、对象、函数、数组等不同的类型
3  name: "test",
4  main: {
5    a: 1,
6    b: 2,
7  },
8  fn: function () {
9    alert(1);
10  },
11  date: new Date(),
12  reg: new RegExp(),
13  friends: [1, 2, 3, [22, 33]],
14};

Copy 
1function clone(obj) {
2  let newObj = {};
3  for (let i in obj) {
4    newObj[i] = obj[i];
5  }
6  return newObj;
7}

Copy 
1function cloneDeep(obj) {
2  let newObj = null;
3  if (typeof obj === "object" && typeof obj !== null) {
4    if (obj instanceof Array) {
5      newObj = [];
6      for (let i in obj) {
7        newObj[i] = cloneDeep(obj[i]);
8      }
9    } else if (obj instanceof Date) {
10      newObj = new Date(obj)
11    } else if (obj instanceof RegExp) {
12      newObj = new RegExp(obj)
13    } else {
14      newObj = {};
15      for (let i in obj) {
16        newObj[i] = cloneDeep(obj[i]);
17      }
18    }
19  } else {
20    newObj = obj;
21  }
22  return newObj;
23}