Nextjs 14 Router Query Params: A Complete Guide

In Next.js 14, the new router API provides a more straightforward way to handle query parameters.

Query parameters are added to the URL as key-value pairs. For example, the URL `https://example.com/users?name=John&age=30` has two query parameters: `name` and `age`.

You can access query parameters in your Next.js pages using the `useRouter` hook.

You can access router query params using the useRouter hook, specifically the query property. This is demonstrated in Example 1, where a file named [category].js is created in the ‘pages’ directory, and the useRouter hook is used to access the category and any additional query parameters.

The query property returns an object containing the query parameters. For instance, in the example, the URL /shoes?price=under-100&brand=nike would render the ProductsByCategory component, and within that component, you could fetch and display products that are shoes under $100 from Nike.

To access specific query parameters, you can use the query property like an object. For example, to access the price parameter, you would use query.price.

You can also use the router object from the useRouter hook to add categories to the URL as query parameters, as shown in Example 3. This is useful when you need to stay on the current page and update the query parameters without navigating to a new page.

Here's a code snippet demonstrating how to access and use query parameters:

```javascript

const { query } = useRouter();

const price = query.price;

const brand = query.brand;

```

By using the useRouter hook and accessing the query property, you can easily retrieve and use query parameters in your Next.js application.

Server-Side Rendering with GetServerSideProps is a powerful tool in Next.js 14.

You can use the getServerSideProps function to fetch data based on query parameters during server-side rendering. This function runs on the server for each request and receives the context object.

The context object includes the query object, which you can extract to log query parameters and fetch data accordingly.

Next.js provides a feature called static generation, which allows you to pre-render pages at build time. This can improve performance and reduce the load on your server.

getStaticProps is a function used to fetch data at build time, making it an essential part of static generation. You can use it to fetch data from APIs or databases and make it available to your pages.

In getStaticProps, you can access query parameters through the params object provided by the context. This allows you to pre-render pages with dynamic routes.

To use getStaticProps, you need to define the paths that include the query parameters you want to pre-render. This is done using the getStaticPaths function, which is used in conjunction with getStaticProps.

By using getStaticProps and getStaticPaths together, you can create pre-rendered pages with dynamic routes and query parameters. This can significantly improve the performance of your Next.js application.

Dynamic Routing is a powerful feature in Next.js that allows you to create pages that respond to query parameters. To create a dynamic page, you first define the dynamic route using the file naming convention mentioned above.

To access the dynamic segments of the URL as query parameters, you can use the useRouter hook or the context object provided to getServerSideProps or getStaticProps. For example, you can create a file in the 'pages' directory that corresponds to the dynamic segment of the URL, such as [category].js.

Within this file, you can use the useRouter hook to access the dynamic segment and any additional query parameters. For instance, a URL like /shoes?price=under-100&brand=nike would render the ProductsByCategory component, and within that component, you could fetch and display products that are shoes under $100 from Nike.

You can also use the router.push method to navigate to a new page and add a new entry to the browser's history stack. This means that when the user clicks the back button, they will return to the previous page.

Here are some key facts to keep in mind when working with dynamic routing and query parameters:

To update the route and add categories to the URL as query parameters, you can use the router object from the useRouter hook. You can also use the spread operator to keep the router's initial data and only add a new filter query to the query parameters.

You can update the route using the router object from the useRouter hook, adding categories to the URL as query parameters.

This is done by keeping the router's initial data using the spread operator and only adding a new filter query to the query parameters. The shallow flag is used to prevent re-running getStaticProps, getServerSideProps, or getInitialProps whenever the path updates.

To add the ability to save the selected categories from the URL when refreshing the page, you can set your query as the initial state of the selectedCategories. However, you can't do this directly because the useRouter hook returns query parameters as undefined on the first render.

To monitor whether or not the queries are populated, you need to check the router isReady property, which checks the router updates on the client side and returns true if fields are ready to use.

Here are some strategies to preserve query parameters during navigation:

The useRouter hook is a client-side hook that allows you to access the router object within your page components. This hook is part of the Next.js router library.

To use the useRouter hook, you import it from the Next.js router library and use it to retrieve the router object. You then destructure the query object from router to access the query parameters.

Here's a code snippet demonstrating how to use the useRouter hook:

```javascript

import { useRouter } from 'next/router';

const Router = () => {

const router = useRouter();

const query = router.query;

// Use query to access query parameters

};

```

The useRouter hook is a powerful tool for accessing router objects and query parameters in your Next.js applications.