面试题: 深拷贝和浅拷贝 - 图1

    1. function deepClone(obj,hash = new WeakMap()) {
    2.     if(obj == null) return obj
    3.     if(typeof obj !== 'object') return obj
    4.     if(obj instanceof Date) return new Date(obj)
    5.     if(obj instanceof RegExp) return new RegExp(obj)
    6.     if(hash.has(obj)) return hash.get(obj)
    7.     // 处理数组和对象
    8.     let newObj = Array.isArray(obj) ? [...obj] : {...obj}
    9.     hash.set(obj,newObj)
    10.     Object.keys(newObj).forEach(key => {
    11.         newObj[key] = deepClone(newObj[key],hash)
    12.     })
    13.     return newObj
    14. }
    16. let obj = {
    17.     a: [1,2],
    18.     b: function() {
    19.         console.log(11);
    20.     },
    21.     c: new Date(),
    22.     d: new RegExp(),
    23. }
    24. obj.xxx = obj
    26. let newObj = deepClone(obj)
    28. console.log(newObj);