React.memo

React.memo

import React from 'react';
// Generates random colours any time it's called
const randomColour = () => '#' + ((Math.random() * 0xffffff) << 0).toString(16);
// The type of the props
type ButtonProps = React.ButtonHTMLAttributes<HTMLButtonElement>;
// A memoized button with a random background colour
const Button = React.memo((props: ButtonProps) => (
<button onClick={props.onClick} style={{ background: randomColour() }}>
{props.children}
</button>
));

链接