jQuery - Trigger event when an element is removed from the DOM

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I'm trying to figure out how to execute some js code when an element is removed from the page:

jQuery('#some-element').remove(); // remove some element from the page
/* need to figure out how to independently detect the above happened */

is there an event tailored for that, something like:

jQuery('#some-element').onremoval( function() {
    // do post-mortem stuff here
});
16 Answers

You can use jQuery special events for this.

In all simplicity,

Setup:

(function($){
  $.event.special.destroyed = {
    remove: function(o) {
      if (o.handler) {
        o.handler()
      }
    }
  }
})(jQuery)

Usage:

$('.thing').bind('destroyed', function() {
  // do stuff
})

Addendum to answer Pierre and DesignerGuy's comments:

To not have the callback fire when calling $('.thing').off('destroyed'), change the if condition to: if (o.handler && o.type !== 'destroyed') { ... }

There is no built-in event for removing elements, but you can create one by fake-extending jQuery's default remove method. Note that the callback must be called before actually removing it to keep reference.

(function() {
    var ev = new $.Event('remove'),
        orig = $.fn.remove;
    $.fn.remove = function() {
        $(this).trigger(ev);
        return orig.apply(this, arguments);
    }
})();

$('#some-element').bind('remove', function() {
    console.log('removed!');
    // do pre-mortem stuff here
    // 'this' is still a reference to the element, before removing it
});

// some other js code here [...]

$('#some-element').remove();

Note: some problems with this answer have been outlined by other posters.

  1. This won't work when the node is removed via html() replace() or other jQuery methods
  2. This event bubbles up
  3. jQuery UI overrides remove as well

The most elegant solution to this problem seems to be: https://stackoverflow.com/a/10172676/216941

I'm not sure there is an event handle for this, so you would have to keep a copy of the DOM and compare to the existing DOM in some kind of polling loop - which could be quite nasty. Firebug does this though - if you inspect the HTML and run some DOM-changes, it highlights the changes in yellow in the Firebug console for a short time.

Alternatively, you could create a remove function...

var removeElements = function(selector) {
    var elems = jQuery(selector);

    // Your code to notify the removal of the element here...
    alert(elems.length + " elements removed");

    jQuery(selector).remove();
};

// Sample usage
removeElements("#some-element");
removeElements("p");
removeElements(".myclass");

The "remove" event from jQuery works fine, without addition. It might be more reliable in time to use a simple trick, instead of patching jQuery.

Just modify or add an attribute in the element you are about to remove from the DOM. Thus, you can trigger any update function, that will just ignore elements on way to be destroyed, with the attribute "do_not_count_it".

Suppose we have a table with cells corresponding to prices, and that you need to show only the last price: This is the selector to trigger when a price cell is deleted (we have a button in each line of the table doing that, not shown here)

$('td[validity="count_it"]').on("remove", function () {
    $(this).attr("validity","do_not_count_it");
    update_prices();
});

And here is a function that finds the last price in the table, not taking account of the last one, if it was the one that was removed. Indeed, when the "remove" event is triggered, and when this function is called, the element is not removed yet.

function update_prices(){
      var mytable=$("#pricestable");
      var lastpricecell = mytable.find('td[validity="count_it"]').last();
}

In the end, the update_prices() function works fine, and after that, the DOM element is removed.

We can also use DOMNodeRemoved:

$("#youridwhichremoved").on("DOMNodeRemoved", function () {
// do stuff
})

an extension to Adam's answer incase you need to prevend default, here is a work around:

$(document).on('DOMNodeRemoved', function(e){
        if($(e.target).hasClass('my-elm') && !e.target.hasAttribute('is-clone')){
            let clone = $(e.target).clone();
            $(clone).attr('is-clone', ''); //allows the clone to be removed without triggering the function again

            //you can do stuff to clone here (ex: add a fade animation)

            $(clone).insertAfter(e.target);
            setTimeout(() => {
                //optional remove clone after 1 second
                $(clone).remove();
            }, 1000);
        }
    });
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