useEffect snippet

useEffect.js

import React, { useState, useEffect } from "react";
import ReactDOM from "react-dom";
// import "./App.css";

class ExampleClass extends React.Component {
  constructor(props) {
    super(props);
    this.state = { count: 0 };
  }

  componentDidMount() {
    document.title = `You clicked ${this.state.count} times`;
  }

  componentDidUpdate() {
    document.title = `You clicked ${this.state.count} times`;
  }

  render() {
    return (
      <div>
        <p>You clicked {this.state.count} times</p>
        <button
          onClick={() =>
            this.setState({
              count: this.state.count + 1
            })
          }
        >
          Click me!
        </button>
      </div>
    );
  }
}

function Example(props) {
  const [count, setCount] = useState(0);

  useEffect(() => {
    document.title = `You clicked ${count} times`;
  });

  return (
    <div>
      <p>You clicked {count} times</p>
      <button onClick={() => setCount(count + 1)}>Click me!</button>
    </div>
  );
}

function App() {
  return (
    <div>
      <h1>test!</h1>
      <ExampleClass />
      <Example />
    </div>
  );
}

ReactDOM.render(<App />, document.getElementById("root"));