React 中使用 Redux Toolkit 状态管理的实践

//  store/modules/xxx.js

import { createSlice } from '@reduxjs/toolkit';

// 创建一个 slice
const counterSlice = createSlice({
  name: 'counter',  // 定义 slice 的名称
  initialState: {   // 初始化状态
    count: 0,       // 需要被全局维护的数据
  },
  reducers: {       // 定义修改状态的方法
    increment(state) {
      state.count += 1;  // 增加计数
    },
    decrement(state) {
      state.count -= 1;  // 减少计数
    },
    reset(state) {
      state.count = 0;    // 重置计数
    },
  },
});

// 导出 action 对象
export const { increment, decrement, reset } = counterSlice.actions;

// 导出 reducer 函数
export const counterReducer = counterSlice.reducer;

// store/index.js

import { configureStore } from '@reduxjs/toolkit';
import { counterReducer } from './counterSlice';

// 创建根 store
const store = configureStore({
  reducer: {
    counter: counterReducer,  // 将源 reducer 组合到根 store 中
  },
});

export default store;

// index.js

import React from 'react';
import ReactDOM from 'react-dom';
import { Provider } from 'react-redux';
import store from './store';
import App from './App';

ReactDOM.render(
  <Provider store={store}>
    <App />
  </Provider>,
  document.getElementById('root')
);

// App.js

import React from 'react';
import { useSelector, useDispatch } from 'react-redux';
import { increment, decrement, reset } from './counterSlice';

const Counter = () => {
  const count = useSelector(state => state.counter.count);  // 获取状态
  const dispatch = useDispatch();  // 获取 dispatch 函数

  return (
    <div>
      <h1>Count: {count}</h1>
      <button onClick={() => dispatch(increment())}>Increment</button>
      <button onClick={() => dispatch(decrement())}>Decrement</button>
      <button onClick={() => dispatch(reset())}>Reset</button>
    </div>
  );
};

export default Counter;

    addToNum(state, action) {
        state.count = action.payload
    }

dispatch(addToNum(20))

// channelStore.js (源)

// 解构出action对象
const {setChannel} = channelStore.actions

// 封装函数
const fetchChannelList = ()=>{
    return async(dispatch) =>{
        const res = await.get(url) // url是请求后端的地址
        // setChannel是源store在reducer中定义的action对象
        dispatch(setChannel(res.data.channels))
    }
}

// channelStore.js (源)

reducers:{
        setChannels(state,action){
        state.channelList = action.payload
    }
}

// App.js

const dispatch = useDispatch()
useEffect(()=>{
    dispatch(fetchChannelList())
},[dispatch]