如何动态引用对象?

In Javascript, I have an object:

在Javascript中，我有一个对象:

obj = { one: "foo", two: "bar" };

Now, I want do do this

现在，我想这样做

var a = 'two';
if(confirm('Do you want One'))
{
  a = 'one';
}

alert(obj.a);

But of course it doesn't work. What would be the correct way of referencing this object dynamically?

但它当然不起作用。动态引用这个对象的正确方法是什么?

3 个解决方案

#1

short answer: obj[a]

简短的回答:obj[一]

long answer: obj.field is just a shorthand for obj["field"], for the special case where the key is a constant string without spaces, dots, or other nasty things. in your question, the key wasn't a constant, so simply use the full syntax.

长答:obj。字段只是obj["field"]的简写，在特殊情况下，键是一个常量字符串，没有空格、点或其他讨厌的东西。在您的问题中，键不是常量，因此只需使用完整的语法。

#2

Like this:

是这样的:

obj[a]

#3

As a side note, global variables are attached to the "window" object, so you can do

作为补充说明，全局变量附加到“窗口”对象，因此您可以这样做

var myGlobal = 'hello';
var a = 'myGlobal';
alert(window[a] + ', ' + window.myGlobal + ', ' + myGlobal);

This will alert "hello, hello, hello"

它会提示“你好，你好，你好”

#1