Create an Object From Two Arrays in JavaScript

In JavaScript, you can create an object from two arrays by using one array for keys and the other for their corresponding values.

• Each element of the first array becomes an object key.
• The element at the same index in the second array becomes its value.
• Methods such as forEach(), reduce(), Object.assign(), and Object.fromEntries() can be used.

Approach 1: Using forEach()

The forEach() method iterates through the keys array and uses the index to access the corresponding value from the second array.

Example: In this example, we use forEach() to create an object from two arrays.

//Driver Code Starts
const a1 = ['name', 'age', 'city'];
const a2 = ['Alen', 25, 'New Delhi'];

//Driver Code Ends

const res = {};

a1.forEach((key, index) => {
    res[key] = a2[index];

//Driver Code Starts
});

console.log(res);
//Driver Code Ends

{ name: 'Alen', age: 25, city: 'New Delhi' }

Approach 2: Using reduce()

The reduce() method can build the object by using an empty object as the accumulator and adding each key-value pair to it.

Example: In this example, we use reduce() to create an object from two arrays.

//Driver Code Starts
const a1 = ['name', 'age', 'city'];
const a2 = ['Alen', 25, 'New Delhi'];

//Driver Code Ends

const res = a1.reduce((obj, key, index) => {
    obj[key] = a2[index];
    return obj;
}, {});

//Driver Code Starts

console.log(res);
//Driver Code Ends

{ name: 'Alen', age: 25, city: 'New Delhi' }

Approach 3: Using Object.assign()

The Object.assign() method can merge multiple objects into a single object. We can use map() to create individual key-value objects and then merge them.

Example: In this example, we use Object.assign() to combine the key-value pairs.

//Driver Code Starts
const a1 = ['name', 'age', 'city'];
const a2 = ['Alen', 25, 'New Delhi'];

//Driver Code Ends

const res = Object.assign(
    {},

//Driver Code Starts
    ...a1.map((key, index) => ({
        [key]: a2[index]
    }))
);

console.log(res);
//Driver Code Ends

{ name: 'Alen', age: 25, city: 'New Delhi' }

Approach 4: Using Object.fromEntries()

The Object.fromEntries() method converts an iterable of key-value pairs into an object. It provides a concise way to combine two arrays.

Example: In this example, we use map() to create key-value pairs and Object.fromEntries() to create the object.

const a1 = ['name', 'age', 'city'];
const a2 = ['Alen', 25, 'New Delhi'];

const res = Object.fromEntries(
    a1.map((key, index) => [key, a2[index]])
);

console.log(res);