浅拷贝 &&&深拷贝 实现

1.浅拷贝

//1.直接赋值给一个变量   //浅拷贝
//2.Object.assign()    //浅拷贝
    let obj4={}
    let obj5={money:50000}
    obj4.__proto__ = obj5
    console.log(obj4)
    console.log(obj4.money)
    let obj6 ={name:'kebo',age:40}
    console.log(Object.assign(obj5,obj6))
//3.Array.prototype.concat()  //浅拷贝
    let arr =[1,2,'wede',{userName:'kobe'} ]
    let arr2 =arr.concat()
//4.Array.prototype.slice()  //浅拷贝
    let arr3 =arr.slice()
//5.JSON.parse(JSON.stringify()) //深拷贝
    let arr4 =JSON.parse(JSON.stringify(arr))

 

2.深度拷贝的实现

//1. 判断数据的类型
function checkType(target){
    return Object.prototype.toString.call(target).slice(8,-1)
}

//2.定义拷贝函数
function clone(target){
    let result,targetType =checkType(target);
    if( targetType==='Object'){
        result = {};
    }else if(targetType ==="Array"){
        result = [];
    }else{
        return target;
    }
    //遍历数据结构中的每一项值
    for(let i in target){
        let value = target[i]
        if(checkType(value)==='Object' || checkType(value)==='Arrary'){
            //继续遍历获取到的值
            clone(value)
        }else{
            result[i]=value
        }
    }
    return result;
}