function Mailbox(props) {
const unreadMessages = props.unreadMessages;
return (
<div>
<h1>Hello!</h1>
{unreadMessages.length > 0 &&
<h2>
You have {unreadMessages.length} unread messages.
</h2>
}
</div>
);
}
Operator
값이 작동안좋은 예 (아래와 같은 경우에 사용)
{unreadMessages.length > 0 ? (
<h2>
You have {unreadMessages.length} unread messages.
</h2>
) : null
}
Reference
https://reactjs.org/docs/conditional-rendering.html#inline-if-with-logical--operator