Object.assign覆蓋原始引用？

Question

我試圖用Object.assign()「合併」兩個對象，但不知何故原始對象被覆蓋。見例如：

var x = {x:1}; 
 
var y = {y:2}; 
 

 
var z = Object.assign(x, y); 
 

 
// what I've expected 
 
console.log(z); // {"x": 1, "y": 2} 
 

 
// what I haven't expected 
 
console.log(x); // {"x": 1, "y": 2}

Answer 1

一個空的對象必須爲Object.assign爲新的合併對象的第一個參數被創建來提供。

var x = { 
 
    x: 1 
 
}; 
 
var y = { 
 
    y: 2 
 
}; 
 

 
var z = Object.assign({}, x, y); 
 

 
// new object 
 
console.log(z); // {"x": 1, "y": 2} 
 

 
// still the same 
 
console.log(x); // {"x": 1} 
 
console.log(y); // {"y": 2}

You can read more information about Object.assign here.

Answer 2

您需要更改像下面

var z = Object.assign({},x, y); 

這裏是工作的jsfiddle：https://jsfiddle.net/ht7jumh6/

Answer 3

傳遞一個空{}到assign()作爲第一參數。

var x = {x:1}; 
 
var y = {y:2}; 
 

 
var z = Object.assign({},x, y); 
 

 
console.log(z); // {"x": 1, "y": 2} 
 

 
console.log(x); // {"x": 1}