can you catch all errors of a React.js app with a try/catch block?

Question

I've made a react application which is not running live, and the people that use it note that very occasionally some strange error occurs. I don't know why or what happens, and can't reproduce it.

So I'm wondering if there is a way to wrap the entire app, or parts of it, in a try/catch block so that I can send the errors to an error log on the server?

All I've read so far is that you could wrap the entire render function in a try/catch, but that would not catch any errors due to user interation right?

Answer 1

Edit

The below solution catches only render errors because they are sync in nature. That is how JS works, it has nothing to do with React, which is what the OP asked about.

Original post

React 16 introduced Error Boundaries and the componentDidCatch lifecycle method:

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

  componentDidCatch(error, info) {
    // Display fallback UI
    this.setState({ hasError: true });
    // You can also log the error to an error reporting service
    logErrorToMyService(error, info);
  }

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

Then you can use it as a regular component:

<ErrorBoundary>
  <MyWidget />
</ErrorBoundary>

Or you can wrap your root component with the npm package react-error-boundary, and set a fallback component and behavior.

import {ErrorBoundary} from 'react-error-boundary';

const myErrorHandler = (error: Error, componentStack: string) => {
  // ...
};

<ErrorBoundary onError={myErrorHandler}>
  <ComponentThatMayError />
</ErrorBoundary>