I am using Sitecore 10.3.1 with JSS-Next.js app version 21.5.3 and Node version 21.7.3.

My requirement is to handle client and server errors at the component level. I am currently using the "?" operator to check for null exceptions, but I need a way to handle other exceptions and display a custom error message within the component.

Here is My code files

/Components/Error.tsx

import React, { ReactNode } from 'react';

interface ErrorBoundaryProps {   children: ReactNode; }

interface ErrorBoundaryState {   hasError: boolean; }

class ErrorBoundary extends React.Component<ErrorBoundaryProps, ErrorBoundaryState> {   constructor(props: ErrorBoundaryProps) {
    super(props);
    this.state = { hasError: false };   }

  static getDerivedStateFromError(): ErrorBoundaryState {
    // Update state so the next render will show the fallback UI.
    return { hasError: true };   }

  componentDidCatch(error: Error, errorInfo: React.ErrorInfo): void {
    // You can also log the error to an error reporting service
    console.error('ErrorBoundary caught an error', error, errorInfo);   }

  render() {
    if (this.state.hasError) {
      // You can render any custom fallback UI
      return <h1>Something went wrong.</h1>;
    }

    return this.props.children;   } }

export default ErrorBoundary;

Pages/_app.tsx

import type { AppProps } from 'next/app';
import { I18nProvider } from 'next-localization';
import { SitecorePageProps } from 'lib/page-props';
import ErrorBoundary from '../components/Error';
import 'bootstrap/dist/css/bootstrap.css';
import 'slick-carousel/slick/slick.css';
import 'slick-carousel/slick/slick-theme.css';

import 'assets/scss/main.scss';

function App({ Component, pageProps }: AppProps<SitecorePageProps>): JSX.Element {
  const { dictionary, ...rest } = pageProps;

  return (
    // Use the next-localization (w/ rosetta) library to provide our translation dictionary to the app.
    // Note Next.js does not (currently) provide anything for translation, only i18n routing.
    // If your app is not multilingual, next-localization and references to it can be removed.
    <I18nProvider lngDict={dictionary} locale={pageProps.locale}>
      <ErrorBoundary>
        <Component {...rest} />
      </ErrorBoundary>
    </I18nProvider>
  );
}

export default App;

BugComponent.tsx

const BuggyComponent = ({ fields }: HomepageHeroBannerProps): JSX.Element => {
  throw new Error('I crashed!');
  console.log(fields);
  return <div>This will not render</div>;
};

export default withDatasourceCheck()<HomepageHeroBannerProps>(BuggyComponent);

Output