js获取action的返回值

// 定义一个thunk action creator
function fetchPosts() {
  return function(dispatch) {
    // 异步操作，例如从服务器获取数据
    return fetch('/posts')
      .then(response => response.json())
      .then(posts => {
        // 分发一个普通的action来更新状态
        dispatch({ type: 'FETCH_POSTS_SUCCESS', payload: posts });
      })
      .catch(error => {
        // 分发一个错误处理的action
        dispatch({ type: 'FETCH_POSTS_FAILURE', payload: error });
      });
  };
}

// 在组件中使用thunk action creator
import { useDispatch } from 'react-redux';

function MyComponent() {
  const dispatch = useDispatch();

  useEffect(() => {
    dispatch(fetchPosts())
      .then(() => {
        // 这里可以处理异步操作完成后的逻辑
        console.log('Posts fetched successfully');
      })
      .catch(error => {
        console.error('Error fetching posts:', error);
      });
  }, [dispatch]);

  // ...
}

import { useSelector, useDispatch } from 'react-redux';

function MyComponent() {
  const posts = useSelector(state => state.posts);
  const dispatch = useDispatch();

  useEffect(() => {
    dispatch({ type: 'FETCH_POSTS_REQUEST' });
  }, [dispatch]);

  useEffect(() => {
    if (posts.length > 0) {
      console.log('Posts have been updated:', posts);
    }
  }, [posts]);

  // ...
}