useeffect not on mount with cleanup function code example
Example 1: useeffect umnount
useEffect(() => {
return () => {
console.log("cleaned up");
};
}, []);
Example 2: useeffect cleanup function
function App() {
const [shouldRender, setShouldRender] = useState(true);
useEffect(() => {
setTimeout(() => {
setShouldRender(false);
}, 5000);
}, []);
// don't render
if( !shouldRender ) return null;
// JSX, if the shouldRender is true
return <ForExample />;
}