如何在React Hook中添加自定义className？

import React from 'react';
import { useState } from 'react';

function MyComponent() {
  const [customClass, setCustomClass] = useState('');

  return (
    <div className={customClass}>
      {/* 组件内容 */}
    </div>
  );
}

function MyComponent() {
  const [customClass, setCustomClass] = useState('');

  const addCustomClass = () => {
    setCustomClass('my-custom-class');
  };

  return (
    <div className={customClass}>
      <button onClick={addCustomClass}>添加自定义className</button>
    </div>
  );
}

ReactDOM.render(<MyComponent />, document.getElementById('root'));