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Throttle Event

A "throttled event" executes its handler after a configured waiting time over a time span. This event type is similar to the debounced event, where the major difference is that a throttled event executes its listeners multiple times.

To construct the event listener, the module TYPO3/CMS/Core/Event/ThrottleEvent must be imported. The constructor accepts the following arguments:

  • eventName (string) - the event to listen on

  • callback (function) - the executed event listener when the event is triggered

  • limit (number) - the amount of milliseconds to wait until the event listener is executed again


If an event spans over 2000ms and the wait time is configured to be 100ms, the event listener gets called up to 20 times in total (\(20=\frac{2000}{100}\)).

new ThrottleEvent('mousewheel', function (e) {
  console.log('Executed every 50ms during the overall event time span');
}, 50).bindTo(document.body);