React hooks
From wikinotes
Hooks let you use react state within function components (without classes).
Documentation
available hooks https://reactjs.org/docs/hooks-reference.html docs https://reactjs.org/docs/hooks-overview.html
Example
useState lets you initialize state with a value, and returns a setter.
// copied from official docs function Example() const [count, setCount] = useState(0) // initial state of counter is '0', 'setCount' updates it return ( <div> <p> <button onClick={() =setCount(count + 1)}> Click me </button> </div> ); }
useState
const [count, setCount] = useState(0); // set initial state to '0', 'setCount' is setter const [name, setName] = useState('alex'); // set initial state to 'alex', 'setName is setter
useEffect
Alternative to component-mounting. It is automatically mounted/unmounted.
function MyComponent() { // install side-effect useEffect(() => { document.title = `You clicked ${count} times` }); return ( ... ); }