useMemo
2019-06-22 本文已影响0人
LynnicKwan
const {useState, useMemo} = React
const App = () => {
const [count, setCount] = useState(0)
const someNum = useMemo(() => {
return Math.random()
}, [])
return <div>
<button onClick={() => setCount(count => count + 1)}>点我{count}</button>
<br/>random number: {someNum}
</div>
}
