组件内部的组件

我正在与React合作。js公司

我想在应用程序组件(app.js)内部使用一个组件x,它位于索引内部。js。

它不起作用。 **

Error
Element type is invalid: expected a string (for built-in components) or a class/function (for composite components) but got: undefined. You likely forgot to export your component from the file it's defined in, or you might have mixed up default and named imports.
Check the render method of `App`.

**

指数js公司

    import { StrictMode } from "react";
import { createRoot } from "react-dom/client";

import App from "./App";

const rootElement = document.getElementById("root");
const root = createRoot(rootElement);

root.render(
  <StrictMode>
    <App />
  </StrictMode>
);

import "./styles.css";
import {SubComponent} from "./components/Subcomponent";

export default function App() {
  return (
    <SubComponent/>
  );
}

子组件

const HelloWorld = ()=>{ return(<p>Hello World !</p>)}
export default HelloWorld();

子组件文件夹为: