Comments on: DOM removal and events

By: That DOM removal thing, again at Nicollet.Net

That DOM removal thing, again at Nicollet.Net — Fri, 22 Jan 2010 09:12:06 +0000

[...] this month, I pondered what looked like a bug in JavaScript/DOM/jQuery: removing an element from the DOM with jQuery (either manually with remove() or by setting the [...]

By: Victor Nicollet

Victor Nicollet — Fri, 08 Jan 2010 10:19:03 +0000

@Adam and Tom: thank you for your answers. I already know why the element itself sticks around and can be inserted into the DOM again: JS is a garbage-collected language, and the DOM elements stay alive as long as they are referenced.

What I don’t know is why the click event I registered on the object disappears.

By: Tom

Tom — Fri, 08 Jan 2010 02:07:38 +0000

Emptying the body doesn’t destroy the reference to the element you created. Imagine creating a variable with a string. Would you expect that to suddenly disappear if you emptied the body? In the same way, the element you created a reference for (in this case button), still exists, with or without the page.

By: adam j. sontag

adam j. sontag — Fri, 08 Jan 2010 00:19:00 +0000

because removing an element from the dom does NOT destroy it. it merely removes the element from the dom. the reference to a button element does not go away just because the body is emptied.

this is useful for working with elements “off of the dom” which will prevent additional reflows and help with performance, for instance.

var foo = $(“#foo”).remove(), width = foo.width();

foo.children(“div”).addClass(“hello”).css(“with”,width);

foo.insertBefore(“#bar”);