JavaScript如何从复制的对象中删除密钥? [英] JavaScript How to delete key from copied object?
问题描述
我有查询对象
var q = {
age: 10,
'profile.contry': 'india'
};
现在我复制 q
变量并删除来自重复变量的密钥。
Now I duplicate the q
variable and remove key from a duplicate variable.
var duplicateQ = q;
delete duplicateQ['profile.contry']; // I have removed 'profile.country' from duplicateQ.
console.log(q); //Object { age: 10 }
console.log(duplicateQ); //Object { age: 10 }
为什么两个变量都受到影响?如何从其中一个属性中删除属性?
Why are both the variables affected? How can I remove the property from only one of them?
推荐答案
您没有重复 q
,相反,你正在复制对不同变量的引用。
You aren't duplicating q
, instead, you're copying a reference to different variable.
两者 q
和 duplicateQ
指向相同的对象,即计算机内存中的相同位置。
Both q
and duplicateQ
point to the same object, the same location in your computer's memory.
为了完成这项工作,你将不得不克隆对象,然后你可以删除(/修改)单独变量上的各个属性。
In order to make this work, you're going to have to clone the object, then you can delete (/ modify) individual properties on the separate variables.
一个快速而肮脏的例子:
A quick-and-dirty example:
var a = { a: 1, b: 2 },
b = JSON.parse(JSON.stringify(a));
delete b.a;
document.body.textContent = JSON.stringify(a) + ' ' + JSON.stringify(b);
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