JavaScript: try...catch

The try...catch statement lets code handle an exception and recover or report a useful failure.

What you will learn

How a try block and catch block work
When finally is useful for cleanup
How to report errors without hiding their cause

Minimal example

try {
  const data = JSON.parse(text);
  showResult(data);
} catch (error) {
  console.error(error);
  showMessage('The data could not be read.');
} finally {
  hideLoadingIndicator();
}

The catch block runs when code in try throws. finally runs whether the operation succeeds or fails, so it is useful for cleanup.

Common mistakes

Do not use an empty catch block; it makes failures invisible.
Do not show raw stack traces or sensitive details to users; log safely and display a useful message.
Catch errors you can handle, and let unexpected failures reach appropriate monitoring.