PerformanceEventTiming: cancelable property

The read-only cancelable property returns the associated event's cancelable property, indicating whether the event can be canceled.

Value

A boolean. true if the associated event is cancelable, false otherwise.

Examples

undefined

Observing non-cancelable events

The cancelable property can be used when observing event-timing entries (PerformanceEventTiming). For example, to log and measure non-cancelable events only.

js
const observer = new PerformanceObserver((list) => {
  list.getEntries().forEach((entry) => {
    if (!entry.cancelable) {
      const delay = entry.processingStart - entry.startTime;
      console.log(entry.name, delay);
    }
  });
});

// Register the observer for events
observer.observe({ type: "event", buffered: true });

Specifications