Convert an object to a Map in JavaScript

To convert an object to a Map in JavaScript, you can use the Object.entries() method to get an array of key-value pairs from the object, and then create a new Map object using the Map constructor and the obtained array.

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

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

const kvPairs = Object.entries(user)

const map = new Map(kvPairs)
console.log(map)

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

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

Alternatively, you can use the Array.forEach() method to iterate over the object keys and add each key-value pair to the Map using the Map.set() method:

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

const map = new Map()

Object.keys(user).forEach(key => {
  map.set(key, user[key])
})

console.log(map)
// Map(3) { 'name' => 'John Doe', 'age' => 20, 'job' => 'Engineer' }

In this example, Object.keys(user) returns an array of keys from the user object. We then iterate over these keys using forEach() and use the Map.set() method to add each key-value pair to the map object.

If you want to convert the Map object back to an object, you can use the Object.fromEntries() method:

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

const user = Object.fromEntries(map)

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

The Object.fromEntries() method takes an iterable of key-value pairs, such as an array, and returns a new object with the key-value pairs.

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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