Next.js has a file-system based router built on the concept of pages.
When a file is added to the pages directory it's automatically available as a route.
The files inside the pages directory can be used to define most common patterns.
The router will automatically route files named index to the root of the directory.
pages/index.js → /pages/blog/index.js → /blogThe router supports nested files. If you create a nested folder structure files will be automatically routed in the same way still.
pages/blog/first-post.js → /blog/first-postpages/dashboard/settings/username.js → /dashboard/settings/usernameTo match a dynamic segment you can use the bracket syntax. This allows you to match named parameters.
pages/blog/[slug].js → /blog/:slug (/blog/hello-world)pages/[username]/settings.js → /:username/settings (/foo/settings)pages/post/[...all].js → /post/* (/post/2020/id/title)Check out the Dynamic Routes documentation to learn more about how they work.
The Next.js router allows you to do client-side route transitions between pages, similarly to a single-page application.
A React component called Link is provided to do this client-side route transition.
import Link from 'next/link'
function Home() {
return (
<ul>
<li>
<Link href="/">
<a>Home</a>
</Link>
</li>
<li>
<Link href="/about">
<a>About Us</a>
</Link>
</li>
<li>
<Link href="/blog/hello-world">
<a>Blog Post</a>
</Link>
</li>
</ul>
)
}
export default Home
In the example above we have multiple links, each one maps a path (href) to a known page:
/ → pages/index.js/about → pages/about.js/blog/hello-world → pages/blog/[slug].jsYou can also use interpolation to create the path, which comes in handy for dynamic route segments. For example, to show a list of posts which have been passed to the component as a prop:
import Link from 'next/link'
function Posts({ posts }) {
return (
<ul>
{posts.map((post) => (
<li key={post.id}>
<Link href={`/blog/${encodeURIComponent(post.slug)}`}>
<a>{post.title}</a>
</Link>
</li>
))}
</ul>
)
}
export default Posts
encodeURIComponentis used in the example to keep the path utf-8 compatible.
Alternatively, using a URL Object:
import Link from 'next/link'
function Posts({ posts }) {
return (
<ul>
{posts.map((post) => (
<li key={post.id}>
<Link
href={{
pathname: '/blog/[slug]',
query: { slug: post.slug },
}}
>
<a>{post.title}</a>
</Link>
</li>
))}
</ul>
)
}
export default Posts
Now, instead of using interpolation to create the path, we use a URL object in href where:
pathname is the name of the page in the pages directory. /blog/[slug] in this case.query is an object with the dynamic segment. slug in this case.To access the router object in a React component you can use useRouter or withRouter.
In general we recommend using useRouter.
The router is divided in multiple parts: