javascript dictionary get key by value code example

Example 1: how to find the key of an value in an object

function getKeyByValue(object, value) {
  return Object.keys(object).find(key => object[key] === value);
}


const map = {"first" : "1", "second" : "2"};
console.log(getKeyByValue(map,"2"));

Example 2: js dictionary to extract the same key bvalues

const car = [{id: "1", brand: "Opel"}, {id: "2", brand: "Haima"},{id: "3", brand: "Toyota"}];

const brands = car.map(({ brand }) => brand);