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HTML

              
                <div id="root">
  <!-- This div's content will be managed by React. -->
</div>
              
            
!

CSS

              
                
              
            
!

JS

              
                class ErrorBoundary extends React.Component {
  constructor(props) {
    super(props);
    this.state = { error: null, errorInfo: null };
  }
  
  componentDidCatch(error, errorInfo) {
    // Catch errors in any components below and re-render with error message
    this.setState({
      error: error,
      errorInfo: errorInfo
    })
    // You can also log error messages to an error reporting service here
  }
  
  render() {
    if (this.state.errorInfo) {
      // Error path
      return (
        <div>
          <h2  style={{ color: 'red' }}>Something went wrong.</h2>
          <details style={{ whiteSpace: 'pre-wrap', border: '2px solid black', borderRadius: '5px', padding: '10px', background: 'pink' }}>
            <span>{this.state.error && this.state.error.toString()}</span>
            <br />
            {this.state.errorInfo.componentStack}
          </details>
        </div>
      );
    }
    // Normally, just render children
    return this.props.children;
  }  
}

class Counter extends React.Component {
  constructor(props) {
    super(props);
    this.state = { counter: 0 };
    this.handleClick = this.handleClick.bind(this);
  }
  
  handleClick() {
    this.setState(({counter}) => ({
      counter: counter + 1
    }));
  }
  
  render() {
    if (this.state.counter === 5) {
      // Simulate a JS error
      throw new Error('I crashed!');
    }
    return <h1 onClick={this.handleClick}>{this.state.counter}</h1>;
  }
}

function App() {
  return (
    <div>
      <p>
        <b>
          Click on the numbers to increase the counters.
          <br />
          This will throw an error when the counter reaches 5.
        </b>
      </p>
      <hr />
      
      <ErrorBoundary>
        <Counter />
      </ErrorBoundary>
    </div>
  );
}



ReactDOM.render(
  <App />,
  document.getElementById('root')
);

              
            
!
999px

Console