Listing 6-4: PropTypes Inside a Component's Body

Welcome, frank!

import PropTypes from 'prop-types';
import {Component} from 'react';

class WelcomeClass extends Component {

  static propTypes = {
    firstName: PropTypes.string
  }

  render(){
    return(<h1>Welcome, {this.props.firstName}!</h1>);
  }
}

export default WelcomeClass;