vault backup: 2022-03-29 17:29:34

随时随地/简单的 React 思考 - useReducer.md

@@ -5,7 +5,8 @@
 const [state, dispatch] = useReducer(reducer, initialArg, init);
 ```
 
-React 官网的 useReducer 实现计数器案例
+React 官网的 useReducer 
+
 ```javascript
 const initialState = {count: 0};
 
@@ -30,4 +31,15 @@ function Counter() {
     </>
   );
 }
-```
+```
+
+最简的 useReducer 实践
+
+```javascript
+const [state, dispatch] = useReducer((state, action) => (
+	{ ...state, action }),
+	initState
+)
+```
+
+在这个最简单的事件中，useReducer 就充当了 useState 的替代，dispatch 修改状态，返回最新的 state