Best way to remove an event handler in jQuery?

…衆ロ難τιáo~ 提交于 2019-11-25 21:47:57

问题


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; });

回答1:


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');



回答2:


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.




回答3:


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




回答4:


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.




回答5:


maybe the unbind method will work for you

$("#myimage").unbind("click");



回答6:


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)



回答7:


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.

});​



回答8:


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.




回答9:


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" );




回答10:


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
}



回答11:


Best way to remove inline onclick event is $(element).prop('onclick', null);




回答12:


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...




回答13:


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")



回答14:


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");




回答15:


This also works fine .Simple and easy.see http://jsfiddle.net/uZc8w/570/

$('#myimage').removeAttr("click");



回答16:


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'))




回答17:


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



回答18:


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.




回答19:


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>


来源:https://stackoverflow.com/questions/209029/best-way-to-remove-an-event-handler-in-jquery

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