深拷贝和浅拷贝

• 深拷贝
  在计算机中开辟一块新的内存地址用于存放复制的对象

let obj1  = {
    name:'jack',
    age:15,
    arr:[1,2,3],
};

let obj2 = {};
deepCopy(obj1,obj2);
console.log(obj1);
console.log(obj2);
obj1.age = 20;
console.log(obj1);
console.log(obj2);

function deepCopy(obj1,obj2) {
    for(let i in obj1){
        if(obj1[i].constructor === Array){
            obj2[i]=[];
            obj2[i] = obj1[i];
        }else{
            obj2[i]={};
            obj2[i] = obj1[i];
        }
    }
}

运行结果:

深拷贝运行结果

• 浅拷贝
  只是增加了一个指针指向已存在的内存地址

let oldObj = { a:1, arr: [2,3] };
let shallowObj = oldObj;
console.log(oldObj);
console.log(shallowObj);
oldObj.a = 5;
console.log(oldObj);
console.log(shallowObj);

运行结果

浅拷贝运行结果