对象引用的可变重新分配使其他对象保持不变(没有“传递"分配) [英] Variable re-assignment of object reference leaves other object unaltered (no “transitive” assignment)

问题描述

我有一个要替换的对象.

I have an object that I want to replace.

var obj1 = { x: "a" };
var ref = obj1;
var obj2 = { y: "b" };

obj1 = obj2;

这导致 ref 等同于 {x:"a"} ，但是我希望它也能更改为指向 obj2 以获得与 {y:"b"} 等效的 ref .

This results in ref being equivalent to { x: "a" }, but I want it to get changed as well to point to obj2 to get ref being equivalent to { y: "b" }.

推荐答案

不可能.JS通过引用的副本传递对象，因此在步骤 var ref = obj1 中，您实际上并未像在C语言中那样分配引用指针.而是在创建副本指向类似于 {x:'a'} 的对象的引用.

Not possible. JS passes objects by a copy of the reference, so in the step var ref = obj1 you're not actually assigning a reference pointer like you would in a language like C. Instead you're creating a copy of a reference that points to an object that looks like {x: 'a'}.

有关其他选项，请参见以下答案: https://stackoverflow.com/a/17382443/6415214 .

See this answer for other options you have: https://stackoverflow.com/a/17382443/6415214.

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