Set all Object keys to false

Question

Lets say I have an object

  filter: {
    \"ID\": false,
    \"Name\": true,
    \"Role\": false,
    \"Sector\": true,
    \"Code\": false
  }

Answer 1

Well here's a one-liner with vanilla JS:

Object.keys(filter).forEach(v => filter[v] = false)

It does use an implicit loop with the .forEach() method, but you'd have to loop one way or another (unless you reset by replacing the whole object with a hardcoded default object literal).

Answer 2

If you don't want to modify the array, here's an ES6 alternative that returns a new one:

Object.fromEntries(Object.keys(filter).map((key) => [key, false]))

Explanation:

Object.keys returns the object's keys:

Object.keys({ a: 1, b: 2 }) // returns ["a", "b"]

Then we map the result ["a", "b"] to [key, false]:

["a", "b"].map((key) => [key, false]) // returns [['a', false], ['b', false]]

And finally we call Object.fromEntries that maps an array of arrays with the form [key, value] to an Object:

Object.fromEntries([['a', false], ['b', false]]) // returns { a: false, b: false }

Answer 3

If you're not using ES6, here is its ES5 counterpart.

Object.keys(filter).forEach(function(key, value) {
    return filter[key] = false;
})