更改数组的值更改原始数组 JavaScript

以下代码导致 id 0 中的两个元素都设置为 -，即使我只想将一个元素设置为 -1>.我只是创建了对 labelArray 的引用，还是其他什么?

The following code causes both elements from id 0 to be set to -, even though I want only one to be set to -1. Am I just creating a reference to the labelArray, or is something else?

labelArray.sort(compare);
valueArray = labelArray;
valueArray[0] = '-1';
labelArray[0] = '-';

感谢所有帮助.

更新(2019 年):自从我第一次写这篇文章已经好几年了，ES6 的使用非常普遍.所以，我想回来补充一点，而不是使用接受的答案中推荐的 slice() 方法，您可以改用 数组析构 在下面进行复制:

UPDATE (2019): It's been several years since I first did this post, and ES6 is used pretty much universally. So, I wanted to come back and add that, instead of using the slice() method recommended in the accepted answer, you can instead use array destructing in the following to make a copy:

valueArray = [...labelArray];