React 使用 Redux 实现组件通信的 Demo 示例
在 React 项目中,父子组件通信通常依赖 props
,兄弟组件通信则通过 状态提升 或 Context。但是当应用逐渐复杂时,这种方式会显得繁琐。此时 Redux 就派上用场了 —— 它可以集中管理全局状态,任何组件都能方便地订阅和修改状态。
本文将带你实现一个简单的 计数器 demo,演示 Redux 在 React 中的组件通信。
一、环境准备
安装必要依赖:
npm install @reduxjs/toolkit react-redux
Redux Toolkit(RTK)是 Redux 官方推荐的写法,简化了很多冗余代码。
二、目录结构
src/
store.ts
features/
counter/
counterSlice.ts
CounterA.tsx
CounterB.tsx
App.tsx
index.tsx
hooks.ts
这里我们会写两个兄弟组件:CounterA
和 CounterB
,通过 Redux 实现通信。
三、配置 Redux Store
src/store.ts
import { configureStore } from "@reduxjs/toolkit";
import counterReducer from "./features/counter/counterSlice";
export const store = configureStore({
reducer: {
counter: counterReducer,
},
});
export type RootState = ReturnType<typeof store.getState>;
export type AppDispatch = typeof store.dispatch;
四、定义 Slice(状态逻辑)
src/features/counter/counterSlice.ts
import { createSlice, PayloadAction } from "@reduxjs/toolkit";
import { RootState } from "../../store";
interface CounterState {
value: number;
}
const initialState: CounterState = { value: 0 };
const counterSlice = createSlice({
name: "counter",
initialState,
reducers: {
increment: (state) => {
state.value += 1;
},
decrement: (state) => {
state.value -= 1;
},
addBy: (state, action: PayloadAction<number>) => {
state.value += action.payload;
},
},
});
export const { increment, decrement, addBy } = counterSlice.actions;
export default counterSlice.reducer;
// 选择器
export const selectCount = (state: RootState) => state.counter.value;
五、封装 Typed Hooks(TS推荐)
src/hooks.ts
import { TypedUseSelectorHook, useDispatch, useSelector } from "react-redux";
import type { RootState, AppDispatch } from "./store";
export const useAppDispatch = () => useDispatch<AppDispatch>();
export const useAppSelector: TypedUseSelectorHook<RootState> = useSelector;
六、兄弟组件通信示例
CounterA.tsx
import React from "react";
import { useAppDispatch } from "../../hooks";
import { increment, addBy } from "./counterSlice";
export default function CounterA() {
const dispatch = useAppDispatch();
return (
<div style={{ border: "1px solid #ccc", padding: 10, margin: 10 }}>
<h3>我是 CounterA</h3>
<button onClick={() => dispatch(increment())}>+1</button>
<button onClick={() => dispatch(addBy(5))}>+5</button>
</div>
);
}
CounterB.tsx
import React from "react";
import { useAppSelector } from "../../hooks";
import { selectCount } from "./counterSlice";
export default function CounterB() {
const count = useAppSelector(selectCount);
return (
<div style={{ border: "1px solid #ccc", padding: 10, margin: 10 }}>
<h3>我是 CounterB</h3>
<p>当前计数:{count}</p>
</div>
);
}
七、应用入口
App.tsx
import React from "react";
import CounterA from "./features/counter/CounterA";
import CounterB from "./features/counter/CounterB";
export default function App() {
return (
<div style={{ padding: 20 }}>
<h2>Redux 通信 Demo</h2>
<CounterA />
<CounterB />
</div>
);
}
index.tsx
import React from "react";
import { createRoot } from "react-dom/client";
import { Provider } from "react-redux";
import { store } from "./store";
import App from "./App";
const root = createRoot(document.getElementById("root")!);
root.render(
<Provider store={store}>
<App />
</Provider>
);
八、运行效果
- 点击
CounterA
中的 +1 或 +5 按钮,会触发 Redux 的dispatch
,修改全局状态。 CounterB
会实时响应,展示最新的计数值。
👉 这就实现了 兄弟组件通信,而且随着应用规模扩大,你只需要在需要的地方使用 Redux,不再需要复杂的 props 传递。
九、总结
- 父子通信:直接用 props。
- 兄弟通信:Redux 是一种集中化管理方式,适合跨层级或复杂场景。
- Redux Toolkit 简化了 reducer 和 action 的写法,官方推荐。
- 在更大规模应用中,还可以结合 Redux Persist(持久化存储)、RTK Query(数据请求管理)。