javascript - jQuery checkbox checked state changed event - Stack Overflow

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I want an event to fire client side when a checkbox is checked / unchecked:

$('.checkbox').click(function() {
  if ($(this).is(':checked')) {
    // Do stuff
  }
});

Basically I want it to happen for every checkbox on the page. Is this method of firing on the click and checking the state ok?

I'm thinking there must be a cleaner jQuery way. Anyone know a solution?

I want an event to fire client side when a checkbox is checked / unchecked:

$('.checkbox').click(function() {
  if ($(this).is(':checked')) {
    // Do stuff
  }
});

Basically I want it to happen for every checkbox on the page. Is this method of firing on the click and checking the state ok?

I'm thinking there must be a cleaner jQuery way. Anyone know a solution?

• javascript
• jquery
• event-handling

Share Improve this question Follow edited Jun 30, 2016 at 12:42 Seth 10.5k1010 gold badges4848 silver badges6969 bronze badges asked Dec 7, 2011 at 22:03 AnonyMouseAnonyMouse 18.6k2626 gold badges8181 silver badges132132 bronze badges 2

• 33 @Arif I don't think they're duplicates because the linked question is about getting the state of a checkbox, while this one is about a checked event. – Rachel Commented Oct 22, 2012 at 13:41
• 1 I always have to search for this checked property, there are many ways to achieve this as written here – user3199690 Commented Oct 30, 2014 at 7:11

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13 Answers 13

Sorted by: Reset to default 1444

Bind to the change event instead of click. However, you will probably still need to check whether or not the checkbox is checked:

$(".checkbox").change(function() {
    if(this.checked) {
        //Do stuff
    }
});

The main benefit of binding to the change event over the click event is that not all clicks on a checkbox will cause it to change state. If you only want to capture events that cause the checkbox to change state, you want the aptly-named change event. Redacted in comments

Also note that I've used this.checked instead of wrapping the element in a jQuery object and using jQuery methods, simply because it's shorter and faster to access the property of the DOM element directly.

Edit (see comments)

To get all checkboxes you have a couple of options. You can use the :checkbox pseudo-selector:

$(":checkbox")

Or you could use an attribute equals selector:

$("input[type='checkbox']")

For future reference to anyone here having difficulty, if you are adding the checkboxes dynamically, the correct accepted answer above will not work. You'll need to leverage event delegation which allows a parent node to capture bubbled events from a specific descendant and issue a callback.

// $(<parent>).on('<event>', '<child>', callback);
$(document).on('change', '.checkbox', function() {
    if(this.checked) {
      // checkbox is checked
    }
});

Note that it's almost always unnecessary to use document for the parent selector. Instead choose a more specific parent node to prevent propagating the event up too many levels.

The example below displays how the events of dynamically added dom nodes do not trigger previously defined listeners.

$postList = $('#post-list');

$postList.find('h1').on('click', onH1Clicked);

function onH1Clicked() {
  alert($(this).text());
}

// simulate added content
var title = 2;

function generateRandomArticle(title) {
  $postList.append('<article class="post"><h1>Title ' + title + '</h1></article>');
}

setTimeout(generateRandomArticle.bind(null, ++title), 1000);
setTimeout(generateRandomArticle.bind(null, ++title), 5000);
setTimeout(generateRandomArticle.bind(null, ++title), 10000);

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<section id="post-list" class="list post-list">
  <article class="post">
    <h1>Title 1</h1>
  </article>
  <article class="post">
    <h1>Title 2</h1>
  </article>
</section>

While this example displays the usage of event delegation to capture events for a specific node (h1 in this case), and issue a callback for such events.

$postList = $('#post-list');

$postList.on('click', 'h1', onH1Clicked);

function onH1Clicked() {
  alert($(this).text());
}

// simulate added content
var title = 2;

function generateRandomArticle(title) {
  $postList.append('<article class="post"><h1>Title ' + title + '</h1></article>');
}

setTimeout(generateRandomArticle.bind(null, ++title), 1000); setTimeout(generateRandomArticle.bind(null, ++title), 5000); setTimeout(generateRandomArticle.bind(null, ++title), 10000);

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<section id="post-list" class="list post-list">
  <article class="post">
    <h1>Title 1</h1>
  </article>
  <article class="post">
    <h1>Title 2</h1>
  </article>
</section>

Just another solution

$('.checkbox_class').on('change', function(){ // on change of state
   if(this.checked) // if changed state is "CHECKED"
    {
        // do the magic here
    }
})

If your intention is to attach event only on checked checkboxes (so it would fire when they are unchecked and checked later again) then this is what you want.

$(function() {
    $("input[type='checkbox']:checked").change(function() {

    })
})

if your intention is to attach event to all checkboxes (checked and unchecked)

$(function() {
    $("input[type='checkbox']").change(function() {

    })
})

if you want it to fire only when they are being checked (from unchecked) then @James Allardice answer above.

BTW input[type='checkbox']:checked is CSS selector.

Is very simple, this is the way I use:

JQuery:

$(document).on('change', '[name="nameOfCheckboxes[]"]', function() {
    var checkbox = $(this), // Selected or current checkbox
        value = checkbox.val(); // Value of checkbox

    if (checkbox.is(':checked'))
    {
        console.log('checked');
    }else
    {
        console.log('not checked');
    }
});

Regards!

$(document).ready(function () {
    $(document).on('change', 'input[Id="chkproperty"]', function (e) {
        alert($(this).val());
    });
});

It can also be accomplished as below. When the checkbox is fired, the div or control with #checkbox id is hiddden or is shown otherwise.

 <script>
      $('#checkbox').on('click',function(){
          if(this.checked){
              $('#checkbox').hide();
           }else{
              $('#checkbox').show();
           }
      });
 </script>

This is the solution to find is the checkbox is checked or not. Use the #prop() function//

$("#c_checkbox").on('change', function () {
                    if ($(this).prop('checked')) {
                        // do stuff//
                    }
                });

Action taking based on an event (on click event).

$('#my_checkbox').on('click',function(){
   $('#my_div').hide();
   if(this.checked){
     $('#my_div').show();
   }
});

Without event taking action based on current state.

$('#my_div').hide();
if($('#my_checkbox').is(':checked')){
  $('#my_div').show();
}

Try this "html-approach" which is acceptable for small JS projects

function msg(animal,is) {
  console.log(animal, is.checked);   // Do stuff
}

<input type="checkbox" oninput="msg('dog', this)" />Do you have a dog? <br>
<input type="checkbox" oninput="msg('frog',this)" />Do you have a frog?<br>
...

perhaps this may be an alternative for you.

<input name="chkproperty" onchange="($(this).prop('checked') ? $(this).val(true) : $(this).val(false))" type="checkbox" value="true" />`

Try this jQuery validation

$(document).ready(function() {
  $('#myform').validate({ // initialize the plugin
    rules: {
      agree: {
        required: true
      }

    },
    submitHandler: function(form) {
      alert('valid form submitted');
      return false;
    }
  });

});

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery-validate/1.17.0/jquery.validate.js"></script>

<form id="myform" action="" method="post">
  <div class="buttons">
    <div class="pull-right">
      <input type="checkbox" name="agree" /><br/>
      <label>I have read and agree to the <a href="https://stackexchange.com/legal/terms-of-service">Terms of services</a> </label>
    </div>
  </div>
  <button type="submit">Agree</button>
</form>

the key is: use prop but not attr to query the checked status, e.g.

• correct: jQuery('#my_check_tag').prop('checked') // return correct status
• incorrect: jQuery('#my_check_tag').attr('checked') // always return undefined

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