reactjs functional components vs class components code example

Example 1: class app extends component syntax

class Welcome extends React.Component {
  render() {
    return <h1>Hello, {this.props.name}</h1>;
  }
}

Example 2: functional components react

function Comment(props) {
  return (
    <div className="Comment">
      <div className="UserInfo">
        <img className="Avatar"
          src={props.author.avatarUrl}
          alt={props.author.name}
        />
        <div className="UserInfo-name">
          {props.author.name}
        </div>
      </div>
      <div className="Comment-text">
        {props.text}
      </div>
      <div className="Comment-date">
        {formatDate(props.date)}
      </div>
    </div>
  );
}

Example 3: class to functional component react

// convert a class component to a functional component
class MyComponent extends React.Component {
	state: { 
      name: 'Bob' 
    }
	render() {
      return (
        <p>Hello, my name is {this.state.name}</p>
      );
    }
}

const MyComponent = () => {
  const [name, setName] = React.useState('Bob');
  return (<p>Hello, my name is {name}</p>);
}