在 JavaScript 中使用“defineProperty”后重置对象属性 getter/setter

Question

I want to "reset" the getter/setter after I changed them using "defineProperty".

The output of the example should be 1 -> nope -> 1, but I just get "undefined".

How can I clear the custom getter, so I it will go with the native default getter?

 var obj = { a: '1', b: '2' }; console.log(obj.a); Object.defineProperty(obj, 'a', { get: function(){ return 'nope'; }, configurable: true }); console.log(obj.a); Object.defineProperty(obj, 'a', { get: undefined, configurable: true }); console.log(obj.a);

Answer 1

I don't see how you'd ever get back to your defaults without cloning obj - because that first getter in essence destroys the original value of 'a'; it's the same as saying obj.a = 'nope' .

Something like this will work:

let obj = {
    a: '1',
  b: '2'
};
const objOrig = JSON.parse(JSON.stringify(obj))

console.log(obj.a);

Object.defineProperty(obj, 'a', {
  get: function(){ return 'nope'; },
  configurable: true
});

console.log(obj.a);

obj = JSON.parse(JSON.stringify(objOrig))

console.log(obj.a);

And note if you ever need to delete a getter you can;

delete obj.a

but it won't revert to the original declaration; 'a' is lost at this point.