Include properties conditionally

Written byPhuoc Nguyen

Created

28 Aug, 2023

Tags

JavaScript

To define a property of an object in JavaScript, we typically declare it directly. For example:

const obj = {
    foo: 'Baz',
    bar: 'Qux',
};

Here's an example: we have an object with two properties named `foo` and `bar`, which have the values `Baz` and `Qux`, respectively.

Now, let's say we only want to include the `bar` property if a certain condition is met. The standard approach is to declare the object as a variable using the `let` declaration, and then set the property later.

let obj = {
    foo: 'Bar',
};
if (condition) {
    obj.bar = 'Qux';
}

While the `if` statement approach works, it's not so convenient when we have to conditionally set many properties at once. Additionally, it turns the object from immutable to mutable due to the `let` declaration.

Fortunately, JavaScript offers the object spread syntax, which is quite handy in this scenario. It allows us to selectively include properties from the source objects, depending on our conditions.

To simplify the sample code above, we can use the following code:

const obj = {
    foo: 'Baz',
    ...(condition && { bar: 'Qux' }),
};

#See also

Create an array with conditional elements

If you found this post helpful, please consider giving the repository a star on GitHub or sharing the post on your favorite social networks 😍. Your support would mean a lot to me!

Questions? 🙋

Do you have any questions about front-end development? If so, feel free to create a new issue on GitHub using the button below. I'm happy to help with any topic you'd like to learn more about, even beyond what's covered in this post.

While I have a long list of upcoming topics, I'm always eager to prioritize your questions and ideas for future content. Let's learn and grow together! Sharing knowledge is the best way to elevate ourselves 🥷.

Ask me questions

Newsletter 🔔

If you're into front-end technologies and you want to see more of the content I'm creating, then you might want to consider subscribing to my newsletter.

By subscribing, you'll be the first to know about new articles, products, and exclusive promotions.

Don't worry, I won't spam you. And if you ever change your mind, you can unsubscribe at any time.

Phước Nguyễn

Include properties conditionally

#See also

Questions? 🙋

Recent posts ⚡

Newsletter 🔔