React Route v6 - useRoutes index = true 属性？

Question

In this case, what is the puerpose of "index=true"? why do I use index=true?? (react-router-dom v6 useRoutes)

{
      path: 'dashboard',
      element: (
        <AuthGuard>
          <DashboardLayout />
        </AuthGuard>
      ),
      children: [
           {
          path: 'e-commerce',
          children: [
            { element: <Navigate to="/dashboard/e-commerce/shop" replace />, index: true },
            { path: 'shop', element: <EcommerceShop /> },
            { path: 'product/', element: <EcommerceProductDetails /> },
            { path: 'list', element: <EcommerceProductList /> },
         
          ],
        },

Answer 1

index tells react-router that it should render the provided element when you are at the index of the route .

In this case it will render <Navigate to="/dashboard/e-commerce/shop" replace /> at the /dashboard/e-commerce route. Which will in this case make sure that the user redirects to /dashboard/e-commerce/shop if they ever accidentally land on this route.

---

The concept behind an index route becomes more clear with an example:

<Route path="albums" element={<BaseLayout />}>
  <Route index element={<AlbumsList />} />
  <Route path=":id" element={<AlbumDetail />} />
  <Route path="new" element={<NewAlbumForm />} />
</Route>

At /albums it will render:

<BaseLayout>
  <AlbumsList />
</BaseLayout>

At /albums/some-unique-album-id it will render:

<BaseLayout>
  <AlbumDetail />
</BaseLayout>

At /albums/new it will render:

<BaseLayout>
  <NewAlbumForm />
</BaseLayout>