How to Create a New Map in JavaScript?

In JavaScript, you can create a new Map using the Map constructor. The Map constructor takes an optional iterable object as an argument and creates a new map from it. Here’s an example:

const map = new Map([
  ['firstName', 'John'],
  ['lastName', 'Doe']
]);
console.log(map); // outputs: Map { 'firstName' => 'John', 'lastName' => 'Doe' }

In this example, the Map constructor is called with an array of arrays as its argument. Each inner array represents a key-value pair in the map. The resulting map object is a new Map with two key-value pairs: 'firstName' => 'John' and 'lastName' => 'Doe'.

You can also add key-value pairs to a Map after it has been created, using the set method. Here’s an example:

const map = new Map();
map.set('age', 30);
map.set('gender', 'male');
console.log(map); // outputs: Map { 'age' => 30, 'gender' => 'male' }

In this example, a new Map is created using the Map constructor without any arguments. Two key-value pairs are added to the map using the set method.