Effortless Object Merging Using Spread Syntax in JavaScript

Discover how to merge objects seamlessly with the power of spread syntax in ES6+

Photo by Chris Linnett on Unsplash

Object merging is a common practice when working with JSON data structures in JavaScript applications. Prior to ES6, developers relied on utility libraries like lodash or custom functions to combine objects efficiently. However, since then, the introduction of spread syntax has simplified this task significantly.

This article covers how to leverage the spread operator for smooth object merging in JavaScript.

Prerequisites

To follow along effectively, ensure you have basic knowledge of JavaScript objects and ES6 syntax. Familiarity with popular libraries such as lodash would be beneficial but isn’t required.

Merging Two Simple Objects

Let’s start by understanding how to merge two simple objects using the spread syntax:

const objA = { foo: 'bar', x: 1 };
const objB = { y: 2, z: 3 };

const mergedObj = { ...objA, ...objB };
console.log(mergedObj); // Output: { foo: 'bar', x: 1, y: 2, z: 3 }

In this example, we created two source objects — objA and objB. We then utilized the spread operator (...) before each…