array map return with key and object code example
Example 1: map through keys javascript
var myObject = { 'a': 1, 'b': 2, 'c': 3 };
Object.keys(myObject).map(function(key, index) {
myObject[key] *= 2;
});
console.log(myObject);
// => { 'a': 2, 'b': 4, 'c': 6 }
Example 2: javascript map over new array
// With ES6, you can do this:
[...Array(10)].map((a, b) => a)