在未运行的useEffect中取消Axios请求

import React, { useEffect, useState } from 'react';
import axios from 'axios';

const MyComponent = () => {
  const [data, setData] = useState(null);
  const [cancelToken, setCancelToken] = useState(null);

  useEffect(() => {
    const fetchData = async () => {
      const source = axios.CancelToken.source();
      setCancelToken(source);

      try {
        const response = await axios.get('https://api.example.com/data', {
          cancelToken: source.token
        });
        setData(response.data);
      } catch (error) {
        if (axios.isCancel(error)) {
          console.log('Request canceled', error.message);
        } else {
          console.log('Request failed', error.message);
        }
      }
    };

    fetchData();

    return () => {
      if (cancelToken) {
        cancelToken.cancel('Component unmounted');
      }
    };
  }, []);

  return (
    <div>
      {data ? (
        <ul>
          {data.map(item => (
            <li key={item.id}>{item.name}</li>
          ))}
        </ul>
      ) : (
        <p>Loading...</p>
      )}
    </div>
  );
};

export default MyComponent;