How can I convert a Map to a JavaScript object and vice versa?

Oftentimes, when working with Map objects, we need to convert from or to plain JavaScript objects. This can be useful when you need to use the Map's key-value pairs as an object or vice versa.

Convert a Map to an object

Using Map.prototype.entries(), we can convert a Map to an array of key-value pairs. Then, we can use Object.fromEntries() to convert the array to an object.

const mapToObject = map => Object.fromEntries(map.entries());

mapToObject(new Map([['a', 1], ['b', 2]])); // {a: 1, b: 2}

Convert an object to a Map

Similarly, using Object.entries(), we can convert an object to an array of key-value pairs. Then, we can use the Map() constructor to convert the array to a Map.

const objectToMap = obj => new Map(Object.entries(obj));

objectToMap({a: 1, b: 2}); // Map {'a' => 1, 'b' => 2}