Convert a Map to an object in JavaScript

You can convert a Map object to an object in JavaScript using the Object.fromEntries() method. The Object.fromEntries() method takes an iterable of key-value pairs and returns a new object.

Here's an example of how you can convert a Map to an object using Object.fromEntries():

const map = new Map([
  ['name', 'John Doe'],
  ['age', 20],
  ['job', 'Doctor']
])

const user = Object.fromEntries(map)
console.log(user)
// { name: 'John Doe', age: 20, job: 'Doctor' }

In this example, the Object.fromEntries() method is called with the map object as the argument, which contains key-value pairs. The method converts the map object to an object literal with the same key-value pairs.

The Object.fromEntries() takes an iterable, such as a Map, and returns an object containing the key-value pairs of the iterable:

const kvPairs = [
  ['name', 'John Doe'],
  ['age', 20],
  ['job', 'Doctor']
]

const user = Object.fromEntries(kvPairs)

console.log(user)
// { name: 'John Doe', age: 20, job: 'Doctor' }

In this case, the kvPairs array directly represents the key-value pairs, and Object.fromEntries() converts them into an object.

An alternate approach is to use the Map.forEach() method to iterate over the entries of the Map object and create a new key on the object for each of them:

const map = new Map([
  ['name', 'John Doe'],
  ['age', 20],
  ['job', 'Doctor']
])

const user = {}

map.forEach((value, key) => {
  user[key] = value
})

console.log(user)
// { name: 'John Doe', age: 20, job: 'Doctor' }

If you want to convert the object back to a Map object, you can use the Object.entries() method to get an array of key-value pairs from the object, and then create a new Map using the Map constructor:

const user = {
  name: 'John Doe',
  age: 20,
  job: 'Doctor'
}

const map = new Map(Object.entries(user))
console.log(map)

// Map(3) { 'name' => 'John Doe', 'age' => 20, 'job' => 'Doctor' }

In this example, Object.entries(user) returns an array of key-value pairs, which is then used to create a new Map object.

To learn more about the Map object and how to create collections of key-value pairs in JavaScript, you can refer to this article.

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