Javascript 数组在 Pop 循环时插入内部

Question

我做了这个jsfiddle而且我无法解释为什么以下不会导致 5 个对象的数组都具有不同的 id 属性:

var arr = ["1", "2", "3", "4", "5"];
var clone = {"id": "0", "name":"Matthew"};
var arrObj = [];

var idArr = [];

while((a=arr.pop()) != null){ 
    clone.id = a;
    console.log(clone);
    arrObj.push(clone);
}

console.log(arrObj);

我最终得到的是我的控制台中的以下内容:

Object {id: "5", name: "Matthew"} (index):28
Object {id: "4", name: "Matthew"} (index):28
Object {id: "3", name: "Matthew"} (index):28
Object {id: "2", name: "Matthew"} (index):28
Object {id: "1", name: "Matthew"} (index):28

[Object, Object, Object, Object, Object]

当我打开 5 个克隆对象中的每一个时，它们的“id”值都为“1”

这是为什么？

Answer 1

clone 是一个对象。在 javascript 中，对象通过引用传递，因此您不会在每个索引中传递不同的对象。

这是有用的东西

while((a=arr.pop()) != null){
    var clone = {"id": a, "name":"Matthew"};
    clone.id = a;
    arrObj.push(clone);
}

console.log(arrObj); 

结果:

Array [
    Object {id: "5", name: "Matthew"}
    Object {id: "4", name: "Matthew"}
    Object {id: "3", name: "Matthew"}
    Object {id: "2", name: "Matthew"}
    Object {id: "1", name: "Matthew"}
]