React Js Window Resize Event

<!DOCTYPE html>
<html>
  <head>
    <meta charset="UTF-8" />
    <script src="https://cdnjs.cloudflare.com/ajax/libs/react/17.0.2/umd/react.development.js"></script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/react-dom/17.0.2/umd/react-dom.development.js"></script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/babel-standalone/6.26.0/babel.min.js"></script>
  </head>

<body>
    <div id="app"></div>
    <script type="text/babel">
      const { useState, useEffect } = React;

const App = () => {
        const [windowWidth, setWindowWidth] = useState(window.innerWidth);

useEffect(() => {
          const handleResize = () => {
            setWindowWidth(window.innerWidth);
          };

window.addEventListener("resize", handleResize);

return () => {
            window.removeEventListener("resize", handleResize);
          };
        }, []);

return (
          <div className="container">
            <h3>React js Window Resize Event</h3>
            <p>Window Width: {windowWidth}px</p>
          </div>
        );
      };

ReactDOM.render(<App />, document.getElementById("app"));
    </script>
    <style>
      .container {
        text-align: center;
        box-shadow: 0 1px 2px 0 rgba(0, 0, 0, 0.12),
          0 2px 4px 0 rgba(0, 0, 0, 0.24);
        width: 600px;
        margin: 0 auto;
        padding: 20px;
        display: flex;
        flex-direction: column;
        align-items: center;
        justify-content: center;
      }
    </style>
  </body>
</html>

 
<!DOCTYPE html>
<html>
  <head>
    <meta charset="UTF-8" />
    <script src="https://cdnjs.cloudflare.com/ajax/libs/react/17.0.2/umd/react.development.js"></script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/react-dom/17.0.2/umd/react-dom.development.js"></script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/babel-standalone/6.26.0/babel.min.js"></script>
  </head>
​
  <body>
    <div id="app"></div>
    <script type="text/babel">
      const { useState, useEffect } = React;
​
      const App = () => {
        const [windowWidth, setWindowWidth] = useState(window.innerWidth);
​
        useEffect(() => {
          const handleResize = () => {
            setWindowWidth(window.innerWidth);
          };
​
          window.addEventListener("resize", handleResize);
​
          return () => {
            window.removeEventListener("resize", handleResize);
          };
        }, []);
​
        return (
          <div className="container">
            <h3>React js Window Resize Event</h3>
            <p>Window Width: {windowWidth}px</p>
          </div>
        );
      };
​
      ReactDOM.render(<App />, document.getElementById("app"));
    </script>
    <style>
      .container {
        text-align: center;
        box-shadow: 0 1px 2px 0 rgba(0, 0, 0, 0.12),
          0 2px 4px 0 rgba(0, 0, 0, 0.24);
        width: 600px;
        margin: 0 auto;
        padding: 20px;
        display: flex;
        flex-direction: column;
        align-items: center;
        justify-content: center;
      }
    </style>
  </body>
</html>
​