使用React.lazy时未捕获未定义错误
我正在尝试实现React 文档中提到的基于路由的代码拆分。
这是我在添加惰性实现之前的应用程序。这工作正常:
import Counter from "./Counter";
import Home from "./Home";
import Login from "./Login";
export function App() {
return (
<Router>
<Suspense fallback={<div>"Loading.."</div>}>
<Switch>
<Route exact path="/" component={Home} />
<Route exact path="/login" component={Login} />
<Route exact path="/counter" component={Counter} />
</Switch>
</Router>
);
}
我所做的只是用这个替换了 3 个导入:
import { lazy, Suspense } from "react";
const Home = lazy(() => import("./Home"));
const Login = lazy(() => import("./Login"));
const Counter = lazy(() => import("./Counter"));
此代码构建成功,但浏览器上没有任何渲染,我在控制台中收到此错误:
Uncaught undefined
The above error occurred in one of your React components:
in Unknown (created by Context.Consumer)
in Route (at App.tsx:29)
in Switch (at App.tsx:28)
in Suspense (at App.tsx:27)
in Router (created by BrowserRouter)
in BrowserRouter (at App.tsx:25)
in ErrorBoundary (at App.tsx:24)
in App (at src/index.tsx:19)
in Provider (at src/index.tsx:18)
in StrictMode (at src/index.tsx:17)
难道我做错了什么?
附加上下文:
如果重要的话,组件被命名为默认重新导出的组件,因为这是 React.lazy 所要求的:
export { Home as default } from "./Home";
其中一个组件使用 redux,因此应用程序被包装在一个商店提供程序中:
<Provider store={store}>
<App />
</Provider>
这是我的 tsconfig:
import Counter from "./Counter";
import Home from "./Home";
import Login from "./Login";
export function App() {
return (
<Router>
<Suspense fallback={<div>"Loading.."</div>}>
<Switch>
<Route exact path="/" component={Home} />
<Route exact path="/login" component={Login} />
<Route exact path="/counter" component={Counter} />
</Switch>
</Router>
);
}
和包版本:
"react": "^17.0.1",
"react-dom": "^16.13.1",
"react-redux": "^7.2.1",
"react-scripts": "^4.0.1",
"react-router-dom": "^5.2.0",
"typescript": "^4.1.2",
这是GitHub 上的源代码和可能相关的问题。
回答
在查看了我自己的问题之后,我想出了查看依赖项的方法。我react和react-dom在不同的主要版本上。
这修复了它:
npm i -D react-dom@17.0.1