原生js实现深复制

function deepClone (obj) {
  if (obj === null) { // 如果是null则直接返回
    return obj;
  }
  let copy = Array.isArray(obj) ? [] : {};
  for (let key in obj) {
    if (obj.hasOwnProperty(key)) {
      if (typeof obj[key] === 'object') {
        copy[key] = deepClone(obj[key]);
      } else {
        copy[key] = obj[key];
      }
    }
  }
  console.log(copy);
  return copy;
}
let a = { name: '小明', age: 23, children: [1, { aa: 1 }, 2, 3], fn: function (v) { return v; } };
let b = deepClone(a);
console.log('b', b);