获取您的 React 服务器
import React from 'react';
import ReactDOM from 'react-dom/client';

class Header extends React.Component {
  render() {
    return (
      <h1>This is the content of the Header component</h1>
    );
  }
}

const root = ReactDOM.createRoot(document.getElementById('root'));
root.render(<Header />);

              
localhost:3000