Javascript使变量成为每次被引用时都会自行调用的函数 [英] Javascript make variable a function that calls itself every time it's referenced

问题描述

我想知道是否可以使变量的行为如下:

Hi I would like to know if it is possible to make a variable behave like this:

var someFlag  = true;
var someWidth = (()=>(someFlag) ? 16 : 12)();

console.log(someWidth) // 16

someFlag = false;

console.log(someWidth) // would be nice if it was 12
// right now it still prints 16

像这样可能吗?我也知道someWidth可能是一个函数，想法是我有很多代码需要重构，所以我不想做someWidth();

Is something like this possible? Also I know that someWidth could be a function, the idea is I have a lot of code I would need to refactor so I don't want to do someWidth();

推荐答案

描述对象属性的好方法是

Great way to describe object property is here

var someFlag  = true;
Object.defineProperty(window, 'someWidth', {

  get:()=>someFlag ? 16 : 12

})
console.log(someWidth) // 16

someFlag = false;
console.log(someWidth) // 12

我认为拥有这样的全局变量不是一个好主意.您可以尝试创建自己的对象吗?

I dont think its good idea to have such global variables.You can try to create your own object maybe?

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