how to get key from key value pair in 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: js change key value in object

var object = { boo:true, baa:5 };
console.log(object);
function change() {
  object.boo = false;
  object.baa++;
};
change();
console.log(object);
//Hope this helps!