Set types on useState React Hook with TypeScript
Use this const [user, setUser] = useState<IUser>({name: ‘Jon’}); See the Corresponding Type in DefinitelyTyped
react-hooks
Attempted import error: ‘useHistory’ is not exported from ‘react-router-dom’
In react-router-dom v6 useHistory() is replaced by useNavigate(). You can use: import { useNavigate } from ‘react-router-dom’; const navigate = useNavigate(); navigate(‘/home’);
Invalid hook call. Hooks can only be called inside of the body of a function component
I had this issue when I used npm link to install my local library, which I’ve built using cra. I found the answer here. Which literally says: This problem can also come up when you use npm link or an equivalent. In that case, your bundler might “see” two Reacts — one in application folder … Read more
What is useState() in React?
React hooks are a new way (still being developed) to access the core features of react such as state without having to use classes, in your example if you want to increment a counter directly in the handler function without specifying it directly in the onClick prop, you could do something like: … const [count, … Read more
In general is it better to use one or many useEffect hooks in a single component? [closed]
The pattern that you need to follow depends on your use case. First: You might have a situation where you need to add event listener during the initial mount and clean them up at unmount and another case where a particular listener needs to be cleaned up and re-added on a prop change. In such … Read more
Can I set state inside a useEffect hook
Generally speaking, using setState inside useEffect will create an infinite loop that most likely you don’t want to cause. There are a couple of exceptions to that rule which I will get into later. useEffect is called after each render and when setState is used inside of it, it will cause the component to re-render … Read more
React Hook “useState” is called in function “app” which is neither a React function component or a custom React Hook function
Try to capitalize ‘app’ like const App = props => {…} export default App; In React, components need to be capitalized, and custom hooks need to start with use.
componentDidMount equivalent on a React function/Hooks component?
For the stable version of hooks (React Version 16.8.0+) For componentDidMount useEffect(() => { // Your code here }, []); For componentDidUpdate useEffect(() => { // Your code here }, [yourDependency]); For componentWillUnmount useEffect(() => { // componentWillUnmount return () => { // Your code here } }, [yourDependency]); So in this situation, you need … Read more
React Hooks useState() with Object
You can pass new value like this: setExampleState({…exampleState, masterField2: { fieldOne: “a”, fieldTwo: { fieldTwoOne: “b”, fieldTwoTwo: “c” } }, })
What’s the difference between `useRef` and `createRef`?
The difference is that createRef will always create a new ref. In a class-based component, you would typically put the ref in an instance property during construction (e.g. this.input = createRef()). You don’t have this option in a function component. useRef takes care of returning the same ref each time as on the initial rendering. … Read more