How to merge two objects in Javascript

In this post, I will show you how to merge objects in javascript.

The most straightforward approach is to use ES6 spread operator.
Let’s suppose you have following objects in javascript.

const person = {
  name: 'John',
  age: 21,
};
const address={
  email:'john@example.com',
  city:'NYC.'
}

Now if you want to merge these two objects you can use the spread operator as below

const mergedObject={...person,...address};
console.log(mergedObject);
// OUTPUT
{
name:"John",
age:21,
email:"john@example.com",
city:"NYC"
}

What if both objects have same property then in this case last object property will win.
For example, if you merge the following objects, you will see object2 override the value of the first object

const obj1={
  prop1:'Object1'
};
const obj2= {
  prop1:'Object2'
}
const merged= {...obj1,...obj2};
console.log(merged);
// OUTPUT
{
prop1:"Object2"
}