onject keys in js code example

Example 1: js object keys

var myObj = {no:'u',my:'sql'}
var keys = Object.keys(myObj);//returnes the array ['no','my'];

Example 2: js create object with keys

var users = [{userId: "1", name: 'harald'}, {userId: "2", name: 'jamie'}];    
var obj = {};
users.forEach(user => {
  obj = {
    ...obj,
    [user.userId]: user,
  }
})
console.log(obj)
// {
//   1: {userId: "1", name: "harald"}
//   2: {userId: "2", name: "jamie"}
// }