Next.js Dynamic Imports: Improve Performance by Loading Components on Demand

Introduction

Dynamic imports in Next.js allow you to load JavaScript modules on-demand, which can improve performance by reducing the amount of initial code that needs to be downloaded. Dynamic imports can also help with code splitting, allowing you to load only the necessary code for each page or component.

To get started with dynamic imports in Next.js, follow these steps:

Step 1: Create a new Next.js app

Create a new Next.js app using the following command in your terminal:

npx create-next-app my-app

This will create a new Next.js app in a folder named my-app.

Step 2: Create a dynamic component

Create a dynamic component by creating a new file named MyComponent.js with the following code:

MyComponent.js

export default function MyComponent() {
  return (
    <div>
      <h1>Hello from MyComponent!</h1>
    </div>
  )
}

Step 3: Use dynamic import to load the component

Use dynamic import to load the MyComponent component on-demand. Create a new file named index.js with the following code:

index.js

import dynamic from 'next/dynamic'

const MyComponent = dynamic(() => import('../components/MyComponent'))

function HomePage() {
  return (
    <div>
      <h1>Welcome to my app!</h1>
      <MyComponent />
    </div>
  )
}

export default HomePage

In this code, we import the dynamic function from next/dynamic, which allows us to load the MyComponent component on-demand. We use the dynamic function to create a new component that will load MyComponent when it is needed.

Step 4: Start the development server

Start the development server using the following command in your terminal:

npm run dev

This will start the development server and make your app available at http://localhost:3000.

Step 5: Test dynamic imports

Open your app in a web browser and navigate to the homepage. You should see that the MyComponent component is not loaded until it is needed, and that it is loaded separately from the rest of the app code.

By following these steps, you have successfully implemented dynamic imports in your Next.js app. This feature can help you improve performance by loading code on-demand and reducing the amount of initial code that needs to be downloaded.

Additional notes:

• You can also use dynamic imports with other components, not just the MyComponent example shown here.
• Be careful not to overuse dynamic imports, as it can negatively affect performance if used excessively.
• You can also use dynamic imports to load other types of modules, such as stylesheets or data files.