What are React Hooks and how do I use them with TypeScript?

What are React Hooks and how do I use them with TypeScript?

React Hooks are functions that let you use state and other React features without writing a class. With TypeScript, you can type your hooks for better type safety.

Can you give me an example of a custom hook in TypeScript?

Sure! Here's a simple custom hook that manages a counter:

import { useState } from 'react';

function useCounter(initialValue: number = 0) {
    const [count, setCount] = useState(initialValue);
    const increment = () => setCount(c => c + 1);
    const decrement = () => setCount(c => c - 1);
    return { count, increment, decrement };
}

How do I type the state in a functional component?

You can type the state by using TypeScript's generic types. For example:

const [state, setState] = useState<MyType>(initialValue);

What are some common pitfalls when using hooks with TypeScript?

Common pitfalls include not typing your state correctly, forgetting to include dependencies in the useEffect hook, and misusing the rules of hooks.