PropTypes

Add to favorites

Implement props type-checking with PropTypes

React Hooks Handbook

Intro to React Hooks

3:39

Create your first React app

4:23

React Component

2:54

Styling in React

5:06

Styles and Props

2:22

Understanding Hooks

3:21

useState Hook

2:54

useEffect Hook

3:41

useRef Hook

3:00

Props

3:11

Conditional Rendering

4:21

Load Local Data

4:04

Fetch Data from an API

5:40

Toggle a state

4:05

useInput Hook

6:04

Gatsby and React

6:44

NextJS and React

5:24

React TypeScript Part 1

8:19

React TypeScript Part 2

7:35

useScrollPosition Hook

4:26

useOnScreen hook

8:08

useContext Hook

8:32

Fragments

2:43

Lazy Loading

4:05

React Suspense

3:13

Environment Variables

4:43

Reach Router

5:31

URL Params

4:04

SEO and Metadata

6:47

Favicon

3:03

Dynamic Favicon

2:14

PropTypes

3:54

Custom PropTypes

3:58

useMemo Hook

4:05

forwardRef Hook

3:28

Handling Events

5:44

Spread attributes

3:35

useMousePosition Hook

4:55

useReducer with useContext Part 1

7:33

useReducer with useContext Part 2

6:48

useReducer with useContext Part 3

5:43

Netlify

5:08

Gatsby Cloud

6:19

Gatsby Plugin Image

8:11

useOnClickOutside Hook

6:32

useWindowSize Hook

4:14

usePageBottom hook

4:48

useLocalStorage Hook

5:27

Three.js in React Part 1

17:33

Three.js in React Part 2

11:18

CodeSandbox link

You can find the full code for this tutorial, with styling, at https://codesandbox.io/s/proptypes-y3nir.

Install the package

First, we'll need to install the package. If you're using NPM, run the following command in the Terminal to install it.

npm install --save prop-types

Use PropTypes

Create a component where a prop should be passed. In my case, I created a button that requires a title, which is a string, as a prop.

const SubmitButton = (props) => {
  return <button type="button">{props.title}</button>;
};

export default SubmitButton;

Import PropTypes at the top of your component's file.

import PropTypes from "prop-types";

To specify the data type of title, we'll create an object and assign a key-value pair for each prop. We'll save this object in our component's propTypes. If we ever pass another data type than a string to the SubmitButton component, it'll raise an error and tell us that the prop should be a string.

SubmitButton.propTypes = {
  title: PropTypes.string
};

In other words, the syntax for adding PropTypes to our component is like so:

ComponentName.propTypes = {
	prop1: PropTypes.string,
	prop2: PropTypes.number
}

Basic data types in PropTypes

Find below a list of all the data types that are included and supported in PropTypes.

PropTypes.any: The prop can of any data type - usually, this propType shouldn't be used as it defies the purpose of adding PropTypes.
PropTypes.bool: The prop should be a boolean.
PropTypes.number: The prop should be a number.
PropTypes.string: The prop should be a string.
PropTypes.func: The prop should be a function.
PropTypes.array: The prop should be an array.
PropTypes.object: The prop should be an object.
PropTypes.symbol: The prop should be a symbol.

You can learn more about all the other types of props we can define using PropTypes here.

Multiple type validation

If a prop passed to a component can be either a string or a number for example, you can easily specify it using .oneOfType, which requires an array of types:

prop1: PropTypes.oneOfType([
	PropTypes.string,
	PropTypes.number
])

isRequired

If a prop is required, meaning a prop must be passed to this component, you can add the isRequired after defining the PropType.

SubmitButton.propTypes = {
  title: PropTypes.string.isRequired
};

Going further

Using PropTypes is perfect if you're using Vanilla JavaScript, and only use the basic types that are included in the PropTypes package. If you wish to create custom prop types, head over to the Custom PropTypes section of this handbook.

You can also go further by using TypeScript. It's a language based upon JavaScript and has type-checking built-in, meaning that everything should have a type - and you don't need to install PropTypes. You can learn more about it in the React TypeScript Part 1 and Part 2 tutorials of this handbook.

Learn with videos and source files. Available to Pro subscribers only.

Purchase includes access to 50+ courses, 320+ premium tutorials, 300+ hours of videos, source files and certificates.

BACK TO

Dynamic Favicon

Download source files

Download the videos and assets to refer and learn offline without interuption.

Design template

Source code for all sections

Video files, ePub and subtitles

Videos

ePub

Assets

Subtitles

Intro to React Hooks

An overview of React Hooks and the frameworks you can use to build your React application blazingly fast

3:39

Create your first React app

Create your first React project from the Terminal and save it on your local computer

4:23

React Component

Create your first JSX component using React

2:54

Styling in React

How to style your React components using inline styling, separate stylesheets or styled-components

5:06

Styles and Props

Render different styles depending on different properties passed to your component

2:22

Understanding Hooks

Learn about the basics of React Hooks, which introduced at React Conf 2018

3:21

useState Hook

Use the useState hook to manage local state in your React component

2:54

useEffect Hook

Manage with your component's lifecycle with the useEffect hook

3:41

useRef Hook

Learn about the useRef hook, which replaces the JavaScript getElementById way

3:00

Props

Learn about props in React to pass data from parent to child components

3:11

Conditional Rendering

Render different UIs depending on different conditions and states

4:21

Load Local Data

Load local JSON data into your React application

4:04

Fetch Data from an API

Learn the basics of asynchronous functions and promises by fetching data from an API using fetch, useEffect and useState

5:40

Toggle a state

Learn how to toggle a state from true to false and back again

4:05

useInput Hook

Create a hook to get the value and the onChange event of input fields

6:04

Gatsby and React

Create a static content-oriented website using React on Gatsby

6:44

NextJS and React

Create your first NextJS React application

5:24

React TypeScript Part 1

Learn how to create a React TypeScript application using the Create React App, Gatsby and NextJS methods

8:19

React TypeScript Part 2

Learn the basics of TypeScript and how to use TypeScript in a React component

7:35

useScrollPosition Hook

Create a custom hook to listen to the current window position of the user

4:26

useOnScreen hook

Create a custom hook to listen to when an element is visible on screen

8:08

useContext Hook

Manage global states throughout the entire application

8:32

Fragments

Group multiple children together with React Fragments

2:43

Lazy Loading

Lazy Load heavy components to improve performance

4:05

React Suspense

Wait for data with React Suspense and React.lazy

3:13

Environment Variables

Make environment variables secret with a .env file

4:43

Reach Router

Create a multiple-pages React application with Reach Router

5:31

URL Params

Create unique URL with URL Params

4:04

SEO and Metadata

Optimize a React application for search engines with React Helmet

6:47

Favicon

Add an icon to a React website

3:03

Dynamic Favicon

Change the favicon's fill color depending on the user's system appearance

2:14

PropTypes

Implement props type-checking with PropTypes

3:54

Custom PropTypes

Create a custom PropType using a validator function

3:58

useMemo Hook

Prevent unnecessary re-renders when the component stays the same

4:05

forwardRef Hook

Forward a ref to a child component

3:28

Handling Events

How to handle events in React

5:44

Spread attributes

Learn how to make use of the spread operator

3:35

useMousePosition Hook

Detect the user's mouse position on a bound element

4:55

useReducer with useContext Part 1

Create a reducer to be used in a context

7:33

useReducer with useContext Part 2

Incorporate useReducer with useContext

6:48

useReducer with useContext Part 3

Connect the context and reducer with the frontend

5:43

Netlify

Deploy to production using Netlify

5:08

Gatsby Cloud

Deploy to production using Gatsby Cloud

6:19

Gatsby Plugin Image

Use gatsby-plugin-image for automatic image resizing, formatting, and higher performance

8:11

useOnClickOutside Hook

Toggle a modal visibility with a useOnClickOutside hook

6:32

useWindowSize Hook

Create a hook to determine the width and height of the window

4:14

usePageBottom hook

Detect if the user scrolled to the bottom of the page

4:48

useLocalStorage Hook

Store an item in a browser's local storage

5:27

Three.js in React Part 1

Bring your website to life with beautiful 3D objects

17:33

Three.js in React Part 2

Bring your website to life with beautiful 3D objects

11:18

Meet the instructor

We all try to be consistent with our way of teaching step-by-step, providing source files and prioritizing design in our courses.

Stephanie Diep

iOS and Web developer

Developing web and mobile applications while learning new techniques everyday

7 courses - 36 hours

Build Quick Apps with SwiftUI

Apply your Swift and SwiftUI knowledge by building real, quick and various applications from scratch

11 hrs

Advanced React Hooks Handbook

An extensive series of tutorials covering advanced topics related to React hooks, with a main focus on backend and logic to take your React skills to the next level

3 hrs

SwiftUI Concurrency

Concurrency, swipe actions, search feature, AttributedStrings and accessibility were concepts discussed at WWDC21. This course explores all these topics, in addition to data hosting in Contentful and data fetching using Apollo GraphQL

3 hrs

SwiftUI Combine and Data

Learn about Combine, the MVVM architecture, data, notifications and performance hands-on by creating a beautiful SwiftUI application

3 hrs

SwiftUI Advanced Handbook

An extensive series of tutorials covering advanced topics related to SwiftUI, with a main focus on backend and logic to take your SwiftUI skills to the next level

4 hrs

React Hooks Handbook

An exhaustive catalog of React tutorials covering hooks, styling and some more advanced topics

5 hrs

SwiftUI Handbook

A comprehensive series of tutorials covering Xcode, SwiftUI and all the layout and development techniques

7 hrs