04.memo应用案例

// class Greeting extends React.PureComponent {
//   render() {
//     console.log("Greeting was rendered at", new Date().toLocaleTimeString());
//     return <h3>Hello{this.props.name && ', '}{this.props.name}!</h3>;
//   }
// }

const Greeting = React.memo(function Greeting({ name }) { ///
  console.log("Greeting was rendered at", new Date().toLocaleTimeString());
  return <h3>Hello{name && ', '}{name}!</h3>;
});