Setting up Typescript with Nextjs Best Practices

• Why Use TypeScript with Next.js?

Next.js, a React framework known for its server-side rendering (SSR), static site generation (SSG), and file-based routing, works seamlessly with TypeScript. TypeScript brings the following benefits to Next.js projects:

• Static Type Checking: Catch errors at compile time rather than runtime.
• Enhanced Developer Experience: Autocompletion, type inference, and better tooling in IDEs like VSCode.
• Easier Refactoring: With strict types and interfaces, refactoring is safer and easier.
• Improved Collaboration: Type definitions provide better documentation for team members and reduce ambiguity.

• Best Practices for Using TypeScript with Next.js
  • Use strict Mode
    • One of the best practices when using TypeScript is to enable strict mode by setting “strict”: true in your tsconfig.json. This enables various type-checking options such as noImplicitAny, strictNullChecks, and alwaysStrict. These settings ensure that your code is robust and that errors are caught early.
  • Leverage Next.js’s Built-in Types

import { NextPage } from 'next';

const Home: NextPage = () => {

  return <h1>Hello, TypeScript with Next.js!</h1>;

};




export default Home;

• Type Your Props and State

interface Props {

  title: string;

  isVisible: boolean;

}




const MyComponent: React.FC<Props> = ({ title, isVisible }) => {

  return (

    <div>

      {isVisible && <h1>{title}</h1>}

    </div>

  );

};

• Avoid Using any Type
  • TypeScript is most effective when you avoid the any type. Instead, use more specific types or interfaces to represent data. If you absolutely need a fallback type, use unknown over any and perform type checks before using the value.
• Use type and interface for Type Definitions

In TypeScript, both type and interface are used to define custom types. However, they have subtle differences:

• Use interface for defining object shapes and classes.
• Use type for more complex types like unions, intersections, and mapped types.
  • Optimize for Server-Side Rendering (SSR)
    • When using TypeScript with server-side rendering in Next.js, always type your server-side functions (getServerSideProps, getStaticProps) and the data they return. This ensures type safety for your SSR logic.

import { GetServerSideProps } from 'next';




interface PageProps {

  message: string;

}




const HomePage = ({ message }: PageProps) => {

  return <div>{message}</div>;

};




export const getServerSideProps: GetServerSideProps<PageProps> = async () => {

  return {

    props: {

      message: 'Hello from the server!',

    },

  };

};




export default HomePage;

• Conclusion
  • Integrating TypeScript with Next.js provides a robust development environment with static typing, improved developer experience, and better maintainability. By following the setup steps and best practices outlined in this guide, you can leverage the full power of TypeScript in your Next.js projects.