Is there a way to change a variable’s value given its name in a function?

Question

Is what I’m trying to accomplish possible? I hear using globalThis is the best alternative to window, frames, etc. but I can’t get it to function. Any help would be appreciated!

var x = true;
var y = true;

function makeFalse(changeVar) {
  globalThis.changeVar = false;
}

makeFalse("x");
makeFalse("y");

console.log(x); //expecting: false, returning: true
console.log(y); //expecting: false, returning: true

It’s possible (with brackets instead of a dot), but it’s not a good idea. (Even `var` itself is dated, and if you change the `var`s to `let`s, `x` and `y` will stop being properties of the global object.) What are you going to use this ability for? — Ry-, Nov 29 '21 at 06:51
Related: ["Variable" variables in JavaScript](https://stackoverflow.com/q/5187530) and [Use dynamic variable names in JavaScript](https://stackoverflow.com/q/5117127) — VLAZ, Nov 29 '21 at 06:57

Nitheesh · Accepted Answer · 2021-11-29T07:12:10.100

You can update them using global window object or with this or with globalThis inside the function.

this and globalThis inside makeFalse function refers to global window object itself.

var x = true;
var y = true;

function makeFalse(changeVar) {
  // window[changeVar] = false;
  // this[changeVar] = false;
  globalThis[changeVar] = false;
}

makeFalse("x");
makeFalse("y");

console.log(x); //expecting: false, returning: true
console.log(y);

Is there a way to change a variable’s value given its name in a function?

1 Answers1