使用redux中的操作在useEffect中获取数据

// actions.js
export const fetchData = () => ({
  type: 'FETCH_DATA',
});

export const fetchDataSuccess = (data) => ({
  type: 'FETCH_DATA_SUCCESS',
  payload: data,
});

// reducer.js
const initialState = {
  data: [],
  loading: false,
  error: null,
};

const dataReducer = (state = initialState, action) => {
  switch (action.type) {
    case 'FETCH_DATA':
      return { ...state, loading: true };
    case 'FETCH_DATA_SUCCESS':
      return { ...state, loading: false, data: action.payload };
    default:
      return state;
  }
};

export default dataReducer;

// dataSlice.js (使用 Redux Toolkit 简化代码)
import { createSlice, createAsyncThunk } from '@reduxjs/toolkit';
import axios from 'axios';

export const fetchData = createAsyncThunk('data/fetchData', async () => {
  const response = await axios.get('/api/data');
  return response.data;
});

const dataSlice = createSlice({
  name: 'data',
  initialState: {
    data: [],
    loading: false,
    error: null,
  },
  reducers: {},
  extraReducers: (builder) => {
    builder
      .addCase(fetchData.pending, (state) => {
        state.loading = true;
      })
      .addCase(fetchData.fulfilled, (state, action) => {
        state.loading = false;
        state.data = action.payload;
      })
      .addCase(fetchData.rejected, (state, action) => {
        state.loading = false;
        state.error = action.error.message;
      });
  },
});

export default dataSlice.reducer;

// Component.js
import React, { useEffect } from 'react';
import { useDispatch, useSelector } from 'react-redux';
import { fetchData } from './dataSlice';

const DataComponent = () => {
  const dispatch = useDispatch();
  const { data, loading, error } = useSelector((state) => state.data);

  useEffect(() => {
    dispatch(fetchData());
  }, [dispatch]);

  if (loading) return <div>Loading...</div>;
  if (error) return <div>Error: {error}</div>;

  return (
    <div>
      {data.map((item) => (
        <div key={item.id}>{item.name}</div>
      ))}
    </div>
  );
};

export default DataComponent;