Error boundaries are special React components that catch JavaScript errors during rendering, in lifecycle methods, and during the constructor of whole tree below them. They are used to handle errors gracefully by displaying a fallback UI and preventing the entire application from crashing due to unhandled errors.
You can use react-error-boundary package to create error boundaries in your application. It provides a ErrorBoundary
component that you can wrap around any component that might throw an error. The ErrorBoundary
component takes a FallbackComponent
prop that is used to render a fallback UI when an error occurs.
Capturing Errors
import { ErrorBoundary } from 'react-error-boundary';
import { FetchData } from './FetchData';
function ErrorFallback({ error, resetErrorBoundary }) {
return (
<div role="alert">
<p>Something went wrong:</p>
<pre>{error.message}</pre>
<button onClick={resetErrorBoundary}>Try again</button>
</div>
);
}
export function App() {
return (
<ErrorBoundary FallbackComponent={ErrorFallback}>
<FetchData />
</ErrorBoundary>
);
}
This FetchData
component will throw an error when it is rendered, and the ErrorBoundary
component will catch the error and display the ErrorFallback
component.
export function FetchData() {
throw new Error('Error fetching data');
return <p>This will never render</p>;
}