get object key from value javascript 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: get keys objet javascript

var foo = {
  'alpha': 'puffin',
  'beta': 'beagle'
};

var keys = Object.keys(foo);
console.log(keys) // ['alpha', 'beta'] 
// (or maybe some other order, keys are unordered).

Example 3: javascript object get value by key

const person = {
  name: 'Bob',
  age: 47
}

Object.keys(person).forEach((key) => {
  console.log(person[key]); // 'Bob', 47
});

Example 4: object.keys

const object1 = {
  a: 'somestring',
  b: 42,
  c: false
};

console.log(Object.keys(object1));
// expected output: Array ["a", "b", "c"]

Example 5: javascript object get value by key

var obj = {
   a: "A",
   b: "B",
   c: "C"
}

console.log(obj.a);  // return string : A

var name = "a";
console.log(obj[name]);