What are some real-world examples of async validators?

Can you give me some real-world examples of async validators?

Sure! Async validators are often used in forms to check for unique usernames or email addresses. For instance, when a user registers, an async validator can check if the username is already taken by querying the database.

That sounds useful! Can you provide another example?

Absolutely! Another example is validating a credit card number. An async validator can verify if the card number is valid by making a request to a payment gateway.

What about in a React application?

In a React app, you might use async validators with libraries like Formik or React Hook Form to validate fields like email or phone number in real-time as the user types.

Thanks! How do I implement one of these in my project?

To implement an async validator, you can create a function that returns a promise. For example, you can use fetch to check the availability of a username and return a resolved or rejected promise based on the response.