I have an input type="image". This acts like the cell notes in Microsoft Excel. If someone enters a number into the text box that this input-image is paired with, I setup an event handler for the input-image. Then when the user clicks the image, they get a little popup to add some notes to the data.
My problem is that when a user enters a zero into the text box, I need to disable the input-image's event handler. I have tried the following, but to no avail.
$('#myimage').click(function { return false; });
jQuery ≥ 1.7
With jQuery 1.7 onward the event API has been updated, .bind()/.unbind() are still available for backwards compatibility, but the preferred method is using the on()/off() functions. The below would now be,
$('#myimage').click(function() { return false; }); // Adds another click event
$('#myimage').off('click');
$('#myimage').on('click.mynamespace', function() { /* Do stuff */ });
$('#myimage').off('click.mynamespace');
jQuery < 1.7
In your example code you are simply adding another click event to the image, not overriding the previous one:
$('#myimage').click(function() { return false; }); // Adds another click event
Both click events will then get fired.
As people have said you can use unbind to remove all click events:
$('#myimage').unbind('click');
If you want to add a single event and then remove it (without removing any others that might have been added) then you can use event namespacing:
$('#myimage').bind('click.mynamespace', function() { /* Do stuff */ });
and to remove just your event:
$('#myimage').unbind('click.mynamespace');
This wasn't available when this question was answered, but you can also use the live() method to enable/disable events.
$('#myimage:not(.disabled)').live('click', myclickevent);
$('#mydisablebutton').click( function () { $('#myimage').addClass('disabled'); });
What will happen with this code is that when you click #mydisablebutton, it will add the class disabled to the #myimage element. This will make it so that the selector no longer matches the element and the event will not be fired until the 'disabled' class is removed making the .live() selector valid again.
This has other benefits by adding styling based on that class as well.
This can be done by using the unbind function.
$('#myimage').unbind('click');
You can add multiple event handlers to the same object and event in jquery. This means adding a new one doesn't replace the old ones.
There are several strategies for changing event handlers, such as event namespaces. There are some pages about this in the online docs.
Look at this question (that's how I learned of unbind). There is some useful description of these strategies in the answers.
How to read bound hover callback functions in jquery
If you want to respond to an event just one time, the following syntax should be really helpful:
$('.myLink').bind('click', function() {
//do some things
$(this).unbind('click', arguments.callee); //unbind *just this handler*
});
Using arguments.callee, we can ensure that the one specific anonymous-function handler is removed, and thus, have a single time handler for a given event. Hope this helps others.
maybe the unbind method will work for you
$("#myimage").unbind("click");
I had to set the event to null using the prop and the attr. I couldn't do it with one or the other. I also could not get .unbind to work. I am working on a TD element.
.prop("onclick", null).attr("onclick", null)
If event is attached this way, and the target is to be unattached:
$('#container').on('click','span',function(eo){
alert(1);
$(this).off(); //seams easy, but does not work
$('#container').off('click','span'); //clears click event for every span
$(this).on("click",function(){return false;}); //this works.
});
You may be adding the onclick handler as inline markup:
<input id="addreport" type="button" value="Add New Report" onclick="openAdd()" />
If so, the jquery .off() or .unbind() won't work. You need to add the original event handler in jquery as well:
$("#addreport").on("click", "", function (e) {
openAdd();
});
Then the jquery has a reference to the event handler and can remove it:
$("#addreport").off("click")
VoidKing mentions this a little more obliquely in a comment above.
If you use $(document).on() to add a listener to a dynamically created element then you may have to use the following to remove it:
// add the listener
$(document).on('click','.element',function(){
// stuff
});
// remove the listener
$(document).off("click", ".element");
To remove ALL event-handlers, this is what worked for me:
To remove all event handlers mean to have the plain HTML structure without all the event handlers attached to the element and its child nodes. To do this, jQuery's clone() helped.
var original, clone;
// element with id my-div and its child nodes have some event-handlers
original = $('#my-div');
clone = original.clone();
//
original.replaceWith(clone);
With this, we'll have the clone in place of the original with no event-handlers on it.
Good Luck...
Updated for 2014
Using the latest version of jQuery, you're now able to unbind all events on a namespace by simply doing $( "#foo" ).off( ".myNamespace" );
Best way to remove inline onclick event is $(element).prop('onclick', null);
Thanks for the information. very helpful i used it for locking page interaction while in edit mode by another user. I used it in conjunction with ajaxComplete. Not necesarily the same behavior but somewhat similar.
function userPageLock(){
$("body").bind("ajaxComplete.lockpage", function(){
$("body").unbind("ajaxComplete.lockpage");
executePageLock();
});
};
function executePageLock(){
//do something
}
In case .on() method was previously used with particular selector, like in the following example:
$('body').on('click', '.dynamicTarget', function () {
// Code goes here
});
Both unbind() and .off() methods are not going to work.
However, .undelegate() method could be used to completely remove handler from the event for all elements which match the current selector:
$("body").undelegate(".dynamicTarget", "click")
I know this comes in late, but why not use plain JS to remove the event?
var myElement = document.getElementById("your_ID");
myElement.onclick = null;
or, if you use a named function as an event handler:
function eh(event){...}
var myElement = document.getElementById("your_ID");
myElement.addEventListener("click",eh); // add event handler
myElement.removeEventListener("click",eh); //remove it
This also works fine .Simple and easy.see http://jsfiddle.net/uZc8w/570/
$('#myimage').removeAttr("click");
if you set the onclick via html you need to removeAttr ($(this).removeAttr('onclick'))
if you set it via jquery (as the after the first click in my examples above) then you need to unbind($(this).unbind('click'))
All the approaches described did not work for me because I was adding the click event with on() to the document where the element was created at run-time:
$(document).on("click", ".button", function() {
doSomething();
});
My workaround:
As I could not unbind the ".button" class I just assigned another class to the button that had the same CSS styles. By doing so the live/on-event-handler ignored the click finally:
// prevent another click on the button by assigning another class
$(".button").attr("class","buttonOff");
Hope that helps.
Hope my below code explains all.
HTML:
(function($){
$("#btn_add").on("click",function(){
$("#btn_click").on("click",added_handler);
alert("Added new handler to button 1");
});
$("#btn_remove").on("click",function(){
$("#btn_click").off("click",added_handler);
alert("Removed new handler to button 1");
});
function fixed_handler(){
alert("Fixed handler");
}
function added_handler(){
alert("new handler");
}
$("#btn_click").on("click",fixed_handler);
$("#btn_fixed").on("click",fixed_handler);
})(jQuery);
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<button id="btn_click">Button 1</button>
<button id="btn_add">Add Handler</button>
<button id="btn_remove">Remove Handler</button>
<button id="btn_fixed">Fixed Handler</button>
I had an interesting case relevant to this come up at work today where there was a scroll event handler for $(window).
// TO ELIMINATE THE RE-SELECTION AND
// RE-CREATION OF THE SAME OBJECT REDUNDANTLY IN THE FOLLOWING SNIPPETS
let $window = $(window);
$window.on('scroll', function() { .... });
But, to revoke that event handler, we can't just use
$window.off('scroll');
because there are likely other scroll event handlers on this very common target, and I'm not interested in hosing that other functionality (known or unknown) by turning off all of the scroll handlers.
My solution was to first abstract the handler functionality into a named function, and use that in the event listener setup.
function handleScrollingForXYZ() { ...... }
$window.on('scroll', handleScrollingForXYZ);
And then, conditionally, when we need to revoke that, I did this:
$window.off('scroll', $window, handleScrollingForXYZ);
The janky part is the 2nd parameter, which is redundantly selecting the original selector. But, the jquery documentation for .off() only provides one method signature for specifying the handler to remove, which requires this middle parameter to be
A selector which should match the one originally passed to .on() when attaching event handlers.
I haven't ventured to test it out with a null or '' as the 2nd parameter, but perhaps the redundant $window isn't necessary.
I see how you might do this with an onclick event: How do you override inline onclick event?
However there is an event which seems to be bound to a specific HTML element that I would like to remove/nullify.
Here is how it is bound with jQuery:
$('.play-control').bind('click', function(evt){
player.play();
});
Using the SE link I provided above does not "disassociate" the original binding. Seems to only work with onclick events.
How then would I "unbind" an event binding in Javascript (or jQuery)?
You can unbind all click handlers hooked up with jQuery using unbind or, with more up-to-date versions of jQuery, off:
$('.play-control').unbind('click');
// or
$('.play-control').off('click');
But unless you can change that code hooking up that handler, you can't unhook just that specific one without delving into jQuery internal data structures which can change without notice between dot releases.
If you can change that code, here are two ways you could target just that handler:
1. Use a named function:
Hooking it up:
function playClick(evt){
player.play();
}
$('.play-control').on('click', playClick); // Or use `bind`
Unhooking it:
$('.play-control').off('click', playClick); // Or use `unbind`
2. Use an "event namespace":
Hooking it up:
$('.play-control').on('click.play', function(evt){ // Or use `bind`
player.play();
});
Unhooking it:
$('.play-control').off('click.play'); // Or use `unbind`
Note the .play added to click.
More in the documentation: on, off
Event handlers attached with .bind() can be removed with .unbind().
(As of jQuery 1.7, the .on() and .off() methods are preferred to
attach and remove event handlers on elements.) In the simplest case,
with no arguments, .unbind() removes all handlers attached to the
elements: http://api.jquery.com/unbind/
According to Jquery, use of off and on is preferred
$(document).bind('click', '.play-control', function(evt){
player.play();
})
$('.play-control').off('click');
I ask a specific question about jquery scroll events, but it seems like the answer could have implications to jquery events in general (which I am also interested in knowing).
Suppose that jquery plugin A (e.g., jquery.scrollspy.js) binds a scroll event to $(window)
Now say that some site imports plugin A, but it also has its own custom javascript file B, which binds another .scroll() event to $(window).
Later on, javascript file B wants to unbind its own scroll event, and leave jquery plugin A intact. How is this done?
and...
Is this method universal to all jquery events?
jQuery recommends to use on and off instead of bind and unbind.
function scrollEvent()
{
}
$(window).on('scroll',scrollEvent);
$(window).off('scroll',scrollEvent);
http://api.jquery.com/on/
Best to use jQuery's .on() and .off() methods rather than .bind() and .unbind().
As of jQuery 1.7, the .on() method is the preferred method for attaching event handlers to a document.
You can also namespace the event by adding a custom suffix to the event name. You can then access that particular event later (to unbind for example)...
$(window).on('scroll.myscroll', function () {
// do something on scroll event
});
an den...
$(window).off('scroll.myscroll'); // unbind my namespaced scroll event
See https://css-tricks.com/namespaced-events-jquery/
This is easy. Didn't do enough research before asking question:
var fileBScrollEvent = function() {
// do something on scroll event
}
$(window).bind('scroll',fileBScrollEvent);
...later on in the code...
$(window).unbind('scroll',fileBScrollEvent);
I have this:
$(function(){
//remove keydown doSomething2
$("body").keydown(doSomething1);
});
In other view I have this:
$(function(){
//remove keydown doSomething1
$("body").keydown(doSomething2);
});
How to do what's in the comment? With my current code, both doSomething1 and doSomething2 are called. I want do disabled the one I dont need.
To remove an event listener with jQuery, you can use .off():
$("body").off("keydown", doSomething2);
Remember the keydown method is just a shortcut for .on("keydown", ...).
However, to "disable" them it might be easier to have only one handler that executes different things based on the current selected view, or have both of them bound and each with a short check that the right view is currently selected.
If doSomething2 is a function reference, you can use .off() (jQuery 1.7+) or .unbind() to remove jQuery bound event handlers:
$('body').off('keydown', doSomething2);
// or
$('body').unbind('keydown', doSomething2);
Note that execution order will be a factor. If the code to unbind the event handler is run first it will have no effect. In general, jQuery event handlers are triggered in the order they're bound, so if the first code snippet in your question is executed first, this approach won't work (you'll need to re-order it).
try this as below using jQuery:
$(function(){
// this would remove keydown from body
$("body").unbind('keydown', doSomething2);
});
I've been working on some code where I trigger the code on hover/unhover. Then I decided to trigger the same code also on focus/blur. Usually with hover/unhover only, I go for the usual hover comma no unhover format. But this time since I was trying to add focus/blur, I had to use bind and use this.bind with the second part too, like this:
$.fn.gogogo = function (msg) {
$(this).bind("hover focus", function(){
$("#screen").html(msg).show();
});
$(this).bind("unhover blur", function(){
$("#screen").html("").hide();
});
}
The problem was that no matter what I did, hover/unhover didn't take. I had to revert back to mouseover/mouseout like this. The code is identical except for the words hover/unhover vs. mouseover/mouseout
$.fn.gogogo = function (msg) {
$(this).bind("mouseover focus", function(){
$("#screen").html(msg).show();
});
$(this).bind("mouseout blur", function(){
$("#screen").html("").hide();
});
}
I thought hover/unhover was just the jquery abstraction of mouseover/mouseout. How come the behavior is different here: hover/unhover breaks my code, while mouseover/mouseout is ok?
thanks.
There is no event called hover.
The hover method is a convenience method that binds event handler to the mouseenter and mouseleave events.
If you open the jQuery source, you'll see that the hover method is defined like this:
hover: function(fnOver, fnOut) {
return this.mouseenter(fnOver).mouseleave(fnOut);
},
You should bind to the mouseenter and mouseleave events instead.
EDIT: The difference between mouseenter and mouseover is that mouseenter (and mouseleave) don't bubble. This means that you'll get a mouseover event if the mouse moves into any element inside the one you bound to (which is probably not what you want), whereas you'll only get a mouseenter event if the mouse entered that element itself. For an example, see the documentation.
There is no "hover" event. That's just a convenience routine.