How to copy an object in js? (Picture and text tutorial)

The following is what I have compiled for you on how to copy an object in js. Interested students can take a look.

Method 1:

Traverse the properties of the original object and assign them to a new object.

//深复制对象方法    
var cloneObj = function (obj) {  
    var newObj = {};  
    if (obj instanceof Array) {  
        newObj = [];  
    }  
    for (var key in obj) {  
        var val = obj[key];  
        //newObj[key] = typeof val === 'object' ? arguments.callee(val) : val; //arguments.callee 在哪一个函数中运行，它就代表哪个函数, 一般用在匿名函数中。  
        newObj[key] = typeof val === 'object' ? cloneObj(val): val;  
    }  
    return newObj;  
};  
//测试    
var obj = {a:function(){console.log(this.b.c)},b:{c:1}},//设置一个对象  
newObj = cloneObj(obj);//复制对象  
newObj.b.c=2;//给新对象赋新值  
obj.a();//1，不受影响  
newObj.a();//2

Method 2:

Serialize the object and then parse it back. If there is a function in the object, it cannot be copied correctly

var obj = {a:1,b:2}  
var newObj = JSON.parse(JSON.stringify(obj));  
newObj.a=3;  
console.log(obj);  
console.log(newObj);

Method 3:

For the method of array object, use the array method to concat an empty array

var a=[1,2,3];  
var b=a;  
var c=[].concat(a);  
a.push(4);  
console.log(b);  
console.log(c);

The above is what I compiled for everyone. I hope it will be helpful to everyone in the future.

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