在javascript中的范围表现怪异 [英] Scope in javascript acting weird

问题描述

对象在javascript中传递给它们的引用。该物体的意义从任何地方应该反映出来。
在这种情况下，console.log（a）的预期输出是{} {/ b>

Object are passed with their reference in javascript. Meaning change in that object from any where should be reflected. In this case, the expected output was {} for console.log(a)

function change(a,b) {
    a.x = 'added';
    a = b;//assigning a as {} to b
}
a={}
b={}
change(a,b);
console.log(a); //expected {} but output {x:'added'}
console.log(b)

这里发生了什么？据我所知，这不应该是因为功能范围。
谢谢

What is happening here? It should not be because of functional scope as far as I know. Thank you

推荐答案

如果您添加了另一行，您可以更清楚地了解正在发生的事情：

If you added another line you can get a clearer picture of what is happening:

function change(a,b) {
    a.x = 'added';
    a = b;
    a.x = 'added as well';
};
a={};
b={};
change(a,b);
console.log(a);  //{x:'added'}
console.log(b);  //{x:'added as well'}

当你在做 a = b 您将局部变量 a 分配给 b 持有。

When you're doing a = b you're assigning the local variable a to the reference that b is holding.

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