Array to Object Based on Key

Introduction

In this lab, we will explore how to convert an array of objects into an object where each object's key is a specified property value of the original objects. We will achieve this by using the Array.prototype.reduce() method and object destructuring in JavaScript. This lab will help you gain a deeper understanding of how to manipulate and transform data in JavaScript.

Converting an Array to an Object Based on a Specific Key

To convert an array into an object based on a specific key and exclude that key from each value, follow these steps:

• Open the Terminal/SSH and type node to start practicing coding.
• Use Array.prototype.reduce() to create an object from the provided array.
• Use object destructuring to extract the value of the given key and the associated data, and then add the key-value pair to the object.

Here's an example implementation:

const indexOn = (arr, key) =>
  arr.reduce((obj, v) => {
    const { [key]: id, ...data } = v;
    obj[id] = data;
    return obj;
  }, {});

You can then use the function like this:

indexOn(
  [
    { id: 10, name: "apple" },
    { id: 20, name: "orange" }
  ],
  "id"
);
// { '10': { name: 'apple' }, '20': { name: 'orange' } }

Summary

Congratulations! You have completed the Array to Object Based on Key lab. You can practice more labs in LabEx to improve your skills.