Next.js 13 Typescript extend Window object

Next.js 13 TypeScript: Extending the Window Object

If you are working with Next.js 13 and TypeScript, you may come across a situation where you need to extend the Window object. This can be useful when you want to add custom properties or methods to the global window object for your application. In this blog post, we will explore two solutions to extend the Window object in Next.js 13 using TypeScript.

Solution 1: Declaration Merging

The first solution involves using declaration merging to extend the Window interface in TypeScript. Declaration merging allows us to add new properties or methods to an existing interface.

Here’s an example of how you can extend the Window object:

// Extend the Window interface
interface CustomWindow extends Window {
  myCustomProperty: string;
  myCustomMethod: () => void;
}

// Assign the extended Window object to the global window variable
declare global {
  interface Window extends CustomWindow {}
}

// Usage
window.myCustomProperty = "Hello, TypeScript!";
window.myCustomMethod = () => {
  console.log("Custom method called");
};

With this solution, you can now access the custom property and method on the window object throughout your Next.js 13 TypeScript application.

Solution 2: Augmentation Module

The second solution involves using an augmentation module to extend the Window object. An augmentation module allows you to add new properties or methods to an existing module.

Here’s an example of how you can use an augmentation module to extend the Window object:

// Create a new module declaration
declare module "next/app" {
  interface AppProps {
    myCustomProp: string;
  }
}

// Usage
import { AppProps } from "next/app";

const MyApp = ({ myCustomProp }: AppProps) => {
  // Use the custom prop
  return 
{myCustomProp}
;
};

export default MyApp;

In this example, we are extending the AppProps interface from the “next/app” module to add a custom property. You can now use the custom prop in your Next.js 13 TypeScript application.

These are two solutions to extend the Window object in Next.js 13 using TypeScript. Choose the solution that best fits your needs and start extending the global window object in your application.

Happy coding!