💡 Mastering `Object.assign()` in JavaScript

Objects are super powerful in JavaScript.

Sometimes we need to copy values from one object to another or merge multiple objects together.

That’s where 👉 Object.assign() comes in!

🟢 What is Object.assign()?

It’s a built-in method that copies properties from one or more source objects into a target object.

Syntax:

Object.assign(target, ...sources) target → the object where data will be copied into sources → one or more objects to copy from 

🟠 Example 1: Simple Copy

const user = { name: "Ali" }; const extra = { age: 25 }; const result = Object.assign({}, user, extra); console.log(result); // 👉 { name: "Ali", age: 25 } 

💡 We used an empty object {} as the target, so both user and extra got merged into it.

🟠 Example 2: Overwriting Properties

If the same property exists in multiple objects, the last one wins (it overwrites).

const obj1 = { skill: "React" }; const obj2 = { skill: "Node.js" }; const merged = Object.assign({}, obj1, obj2); console.log(merged); // 👉 { skill: "Node.js" } 

⚡ The value from obj2 replaced the value from obj1.

🟠 Example 3: Cloning an Object

We can make a shallow copy of an object like this: const original = { city: "Lahore" }; const clone = Object.assign({}, original); console.log(clone); // 👉 { city: "Lahore" } console.log(original === clone); // 👉 false (different objects in memory) 

✅ The clone has the same data but is a different object in memory.

🟠 Example 4: Multiple Sources

 const a = { x: 1 }; const b = { y: 2 }; const c = { z: 3 }; const all = Object.assign({}, a, b, c); console.log(all); // 👉 { x: 1, y: 2, z: 3 } 

⚠️ Limitations

It only makes a shallow copy (nested objects are still references).

For deep copies, use structuredClone() or libraries like Lodash.

🎯 Final Thoughts

Object.assign() is a simple but powerful tool:

✅ Merge objects

✅ Create shallow copies

✅ Set default values

Keep this handy whenever you’re working with objects in JavaScript ✨

👉 Have you ever used Object.assign() in your projects?
Drop a comment and share your experience 🚀