map function for objects (instead of arrays)

Question

I have an object:

myObject = { \'a\': 1, \'b\': 2, \'c\': 3 }

I am looking for a native method, similar to Array.prototype.map

Answer 1

For maximum performance.

If your object doesn't change often but needs to be iterated on often I suggest using a native Map as a cache.

// example object
var obj = {a: 1, b: 2, c: 'something'};

// caching map
var objMap = new Map(Object.entries(obj));

// fast iteration on Map object
objMap.forEach((item, key) => {
  // do something with an item
  console.log(key, item);
});

Object.entries already works in Chrome, Edge, Firefox and beta Opera so it's a future-proof feature. It's from ES7 so polyfill it https://github.com/es-shims/Object.entries for IE where it doesn't work.