TypeError: Object is not iterable (cannot read property Symbol(Symbol.iterator)) 篮子

Question

为什么会这样？篮子在 {} 中，为什么它不能读取？我试图返回控制台日志，它说的是同样的事情....如果我将它上传到托管 cpanel，那么该网站就是白色的......是否只有这个 app.js 代码弄乱了整个编码？.. ....................

                        import React, {useEffect} from 'react';
                    import './App.css';
                    import Header from './Header';
                    import Home from './Home'
                    import Footer from './Footer';
                    import {BrowserRouter as Router, Switch, Route} from "react-router-dom";
                    import Checkout from './Checkout';
                    import Login from "./Login"
                    import { auth } from './firebase';
                    import { useStateValue } from './Stateprovider';

                    function App() {
                      const [ {basket} , dispatch] = useStateValue();
                      console.log({basket})

                      useEffect(() => {
                        
                        auth.onAuthStateChanged(authUser => {
                          console.log("the user is >>>", authUser);
                          if (authUser){
                            dispatch({
                              type: "SET_USER",
                              user: authUser
                            })
                          } else {
                            dispatch({
                              type: "SET_USER",
                              user: null
                            })
                          }
                        })
                      }, [])

                      return (
                        // BEM
                        <Router>
                          <div className="app">
                            
                          <Header />
                          
                            <Switch>

                            <Route path="/login">
                              <Login/>
                                <Footer />
                              </Route>
                              
                            <Route path="/checkout">
                                <Checkout />
                                <Footer />
                              </Route>
                              
                              <Route path="/">
                                <Home/>
                                <Footer />
                              </Route>


                            </Switch> 
                            {/* Home */}
                        </div>
                        </Router>
                      );
                    }

                    export default App;

Answer 1

去掉basket周围的花括号：

const [basket , dispatch] = useStateValue();
console.log(basket);

写{ basket } 的意思是“从值中提取basket 属性”但没有（只有type 和user 存在）。