Custom PropTypes
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Create a custom PropType using a validator function
React Hooks Handbook
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React Component
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Styling in React
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Styles and Props
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Understanding Hooks
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useState Hook
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useEffect Hook
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useRef Hook
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Props
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Conditional Rendering
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Load Local Data
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Toggle a state
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useInput Hook
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Gatsby and React
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NextJS and React
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React TypeScript Part 1
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React TypeScript Part 2
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useScrollPosition Hook
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useOnScreen hook
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useContext Hook
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URL Params
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29
SEO and Metadata
6:47
30
Favicon
3:03
31
Dynamic Favicon
2:14
32
PropTypes
3:54
33
Custom PropTypes
3:58
34
useMemo Hook
4:05
35
forwardRef Hook
3:28
36
Handling Events
5:44
37
Spread attributes
3:35
38
useMousePosition Hook
4:55
39
useReducer with useContext Part 1
7:33
40
useReducer with useContext Part 2
6:48
41
useReducer with useContext Part 3
5:43
42
Netlify
5:08
43
Gatsby Cloud
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44
Gatsby Plugin Image
8:11
45
useOnClickOutside Hook
6:32
46
useWindowSize Hook
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47
usePageBottom hook
4:48
48
useLocalStorage Hook
5:27
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Three.js in React Part 1
17:33
50
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/custom-proptypes-ue2z0.
The issue
We have a component, called EmailCard, which takes an email as a prop. We defined the email's propType as a string. However, since the email is a string, we can pass in a string like hello, world!, which isn't an email. That's when custom validators come in handy.
import PropTypes from "prop-types";
const EmailCard = ({ email }) => {
return <a href={`mailto:` + email}>{email}</a>;
};
export default EmailCard;
EmailCard.propTypes = {
email: PropTypes.string
};Custom validators
A custom validator is a function that takes three arguments:
- The props, an object containing all the props passed to the component
- The propName, the prop's name
- The componentName, the name of the component.
Inside of the function, we will check if the prop corresponding to the propName is valid, with a regex expression for example. Let's see how to implement that in our example.
The solution
The following function is our custom validator to check if the email prop passed to our EmailCard component is actually an email, using a regex expression. If it's not, we'll throw an error.
const isEmail = (props, propName, componentName) => {
const regex = /^[a-zA-Z0-9.!#$%&’*+/=?^_`{|}~-]+@[a-zA-Z0-9-]+(?:\.[a-zA-Z0-9-]+)*$/;
if (!regex.test(props[propName])) {
return new Error(
`Invalid prop ${propName} passed to ${componentName}. Expected a valid email.`
);
}
};We'll replace the propType of email by this function, and specify that it's required
EmailCard.propTypes = {
email: isEmail
};If we try to pass a string that's not an email, we'll see an error printed in the console.
{/* This passes the custom validator check */}
<EmailCard email="hello@designcode.io" />
{/* This fails the custom validator check */}
<EmailCard email="hello, world!" />
Custom validator check failing
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1
Intro to React Hooks
An overview of React Hooks and the frameworks you can use to build your React application blazingly fast
3:39
2
Create your first React app
Create your first React project from the Terminal and save it on your local computer
4:23
3
React Component
Create your first JSX component using React
2:54
4
Styling in React
How to style your React components using inline styling, separate stylesheets or styled-components
5:06
5
Styles and Props
Render different styles depending on different properties passed to your component
2:22
6
Understanding Hooks
Learn about the basics of React Hooks, which introduced at React Conf 2018
3:21
7
useState Hook
Use the useState hook to manage local state in your React component
2:54
8
useEffect Hook
Manage with your component's lifecycle with the useEffect hook
3:41
9
useRef Hook
Learn about the useRef hook, which replaces the JavaScript getElementById way
3:00
10
Props
Learn about props in React to pass data from parent to child components
3:11
11
Conditional Rendering
Render different UIs depending on different conditions and states
4:21
12
Load Local Data
Load local JSON data into your React application
4:04
13
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
14
Toggle a state
Learn how to toggle a state from true to false and back again
4:05
15
useInput Hook
Create a hook to get the value and the onChange event of input fields
6:04
16
Gatsby and React
Create a static content-oriented website using React on Gatsby
6:44
17
NextJS and React
Create your first NextJS React application
5:24
18
React TypeScript Part 1
Learn how to create a React TypeScript application using the Create React App, Gatsby and NextJS methods
8:19
19
React TypeScript Part 2
Learn the basics of TypeScript and how to use TypeScript in a React component
7:35
20
useScrollPosition Hook
Create a custom hook to listen to the current window position of the user
4:26
21
useOnScreen hook
Create a custom hook to listen to when an element is visible on screen
8:08
22
useContext Hook
Manage global states throughout the entire application
8:32
23
Fragments
Group multiple children together with React Fragments
2:43
24
Lazy Loading
Lazy Load heavy components to improve performance
4:05
25
React Suspense
Wait for data with React Suspense and React.lazy
3:13
26
Environment Variables
Make environment variables secret with a .env file
4:43
27
Reach Router
Create a multiple-pages React application with Reach Router
5:31
28
URL Params
Create unique URL with URL Params
4:04
29
SEO and Metadata
Optimize a React application for search engines with React Helmet
6:47
30
Favicon
Add an icon to a React website
3:03
31
Dynamic Favicon
Change the favicon's fill color depending on the user's system appearance
2:14
32
PropTypes
Implement props type-checking with PropTypes
3:54
33
Custom PropTypes
Create a custom PropType using a validator function
3:58
34
useMemo Hook
Prevent unnecessary re-renders when the component stays the same
4:05
35
forwardRef Hook
Forward a ref to a child component
3:28
36
Handling Events
How to handle events in React
5:44
37
Spread attributes
Learn how to make use of the spread operator
3:35
38
useMousePosition Hook
Detect the user's mouse position on a bound element
4:55
39
useReducer with useContext Part 1
Create a reducer to be used in a context
7:33
40
useReducer with useContext Part 2
Incorporate useReducer with useContext
6:48
41
useReducer with useContext Part 3
Connect the context and reducer with the frontend
5:43
42
Netlify
Deploy to production using Netlify
5:08
43
Gatsby Cloud
Deploy to production using Gatsby Cloud
6:19
44
Gatsby Plugin Image
Use gatsby-plugin-image for automatic image resizing, formatting, and higher performance
8:11
45
useOnClickOutside Hook
Toggle a modal visibility with a useOnClickOutside hook
6:32
46
useWindowSize Hook
Create a hook to determine the width and height of the window
4:14
47
usePageBottom hook
Detect if the user scrolled to the bottom of the page
4:48
48
useLocalStorage Hook
Store an item in a browser's local storage
5:27
49
Three.js in React Part 1
Bring your website to life with beautiful 3D objects
17:33
50
Three.js in React Part 2
Bring your website to life with beautiful 3D objects
11:18
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