# Always remove event listeners?

**URL:** <https://forum.kirupa.com/t/always-remove-event-listeners/315333>\
**Category:** Uncategorized\
**Created:** [October 23, 2010, 2:49am UTC](https://forum.kirupa.com/t/always-remove-event-listeners/315333 "2010-10-23T02:49:01Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![tbo](https://avatars.discourse-cdn.com/v4/letter/t/7feea3/32.png) [@tbo](https://forum.kirupa.com/u/tbo)\
**Post date:** [October 23, 2010, 2:49am UTC](https://forum.kirupa.com/t/always-remove-event-listeners/315333/1 "2010-10-23T02:49:01Z")

</div>

is it necessarily to add and remove event listeners like so:

```auto

addEventListener(MouseEvent.MOUSE_DOWN,mDown);

function mDown(e:MouseEvent){
    removeEventListener(MouseEvent.MOUSE_DOWN,mDown); 
    addEventListener(MouseEvent.MOUSE_UP,mUp);
    //do stuff
}

function mUp(e:MouseEvent){
    removeEventListener(MouseEvent.MOUSE_UP,mUp)
    addEventListener(MouseEvent.MOUSE_DOWN,mDown);
    //do stuff
}

```

assuming rapid input, is it really better to do this rather than just let the mouseDown and MouseUp Listeners run all the time? It \*seems \*like it would be strenuous to constantly add and remove listeners like this. But this is how i generally see it done… (i think)