AbortSignal.reason

The reason read-only property returns a JavaScript value that indicates the abort reason.

The property is undefined when the signal has not been aborted. It can be set to a specific value when the signal is aborted, using AbortController.abort() or AbortSignal.abort(). If not explicitly set in those methods, it defaults to "AbortError" DOMException.

A JavaScript value that indicates the abort reason, or undefined, if not aborted.

In the following snippet, we create a new AbortController object, and get its AbortSignal (available using the signal property). Later on, using the aborted property, we check whether or not the signal has been aborted, and log the abort status and reason to the console.

var controller = new AbortController();
var signal = controller.signal;

// ...

signal.aborted ? console.log(`Request aborted with reason: ${signal.reason}`) : console.log('Request not aborted');

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