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JavaScript JavaScript and the DOM (Retiring) Responding to User Interaction Event Bubbling and Delegation

Amandeep Pasricha
Amandeep Pasricha
14,932 Points

Is an event object always created after an event occurs on an element (mouseover, click)?

Is an event object always created after an event occurs on an element (mouseover, click), even if an event listener is not attached to the child or any ancestor element?

1 Answer

Steven Parker
Steven Parker
217,531 Points

Funny question .. similar to "if no one is around to hear a tree falling in the forest, does it make any sound?" :wink:

It would probably depend on the specific JavaScript engine. But I would suspect that in the interest of efficiency, the event mechanisms (including event object creation) are bypassed when there are no listeners to process the event.