useEffect , memo

button import Button from "./components/Button"; import { createContext, useReducer,useState } from "react"; export const UserContext = createContext(null); export default function App() { const reducer = (current_state, action )=> { switch (action.type){ case "ADD": return [...current_state, action.xxx]; case "DEL": return [current_state.filter((v,i) => v !== action.xxx)]; default: return curre..

2024.03.19