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Performance difference between jQuery"s .live("click", fn) and .click(fn)



I love the new live event in jQuery 1.3. The question I have is the performance of this event. I know the advantages of using live over click/bind('click') but is there a performance hit for using it over click/bind('click')?





If not, why would you ever use click or bind('click')?



Source: Tips4all

Comments

  1. If not, why would you ever use click
    or bind('click')?


    Because $.live() has some significant disadvantages



    Live events do not bubble in the traditional manner and cannot be
    stopped using stopPropagation or
    stopImmediatePropagation. For example,
    take the case of two click events -
    one bound to "li" and another "li a".
    Should a click occur on the inner
    anchor BOTH events will be triggered.
    This is because when a
    $("li").bind("click", fn); is bound
    you're actually saying "Whenever a
    click event occurs on an LI element -
    or inside an LI element - trigger this
    click event." To stop further
    processing for a live event, fn must
    return false.
    Live events currently only work when used against a selector. For
    example, this would work: $("li
    a").live(...) but this would not:
    $("a", someElement).live(...) and
    neither would this:
    $("a").parent().live(...).

    ReplyDelete
  2. See this.

    As for why you would ever use click or bind instead of live, the answer is because you don't need the extra functionality.

    ReplyDelete
  3. You should read this very good answer in this similar thread:

    Is binding events in jQuery very expensive, or very inexpensive?

    ReplyDelete
  4. Just a notice: there is a firebug extension which shows all attached events on a page: http://robertnyman.com/inline-code-finder/

    ReplyDelete

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