jQuery set checkbox checked


I already tried all the possible ways, but I still didn't get it working. I have a modal window with a checkbox I want that when the modal opens, the checkbox check or uncheck should be based on a database value. (I have that already working with others form fields.) I started trying to get it checked but it didn't work.

My HTML div:

<div id="fModal" class="modal" >
    <div class="row-form">
        <div class="span12">
            <span class="top title">Estado</span>
          <input type="checkbox"  id="estado_cat" class="ibtn">

and the jQuery:

$("#estado_cat").prop( "checked", true );

I also tried with attr, and others seen here in the forums, but none seem to work.
Can someone point me the right way?


OK, I'm really missing something here. I can check/uncheck using code if the check box is in the page, but is it's in the modal window, I can't. I tried dozens of different ways.

I have a link that's supposed to open the modal:

<a href='#' data-id='".$row['id_cat']."' class='editButton icon-pencil'></a>

and jQuery to "listen" the click and execute some operations like filling some text boxes with data coming from database. Everything works like I want but the problem is that I can't set checkbox checked/unchecked using code. Help please!

$(function () {
    $(".editButton").click(function () {
        var id = $(this).data('id');
            type: "POST",
            url: "process.php",
            dataType: "json",
            data: {
                id: id,
                op: "edit"
        }).done(function (data) {
            // The next two lines work fine,
            // i.e. it grabs the value from database and fills the textboxes

            // Then I tried to set the checkbox checked (because it's unchecked by default)
            // and it does not work
            $("#estado_cat").prop("checked", true);
        return false;
6/22/2020 7:54:36 PM

Taking all of the proposed answers and applying them to my situation - trying to check or uncheck a checkbox based on a retrieved value of true (should check the box) or false (should not check the box) - I tried all of the above and found that using .prop("checked", true) and .prop("checked", false) were the correct solution.

I can't add comments or up answers yet, but I felt this was important enough to add to the conversation.

Here is the longhand code for a fullcalendar modification that says if the retrieved value "allDay" is true, then check the checkbox with ID "even_allday_yn":

if (allDay)
    $( "#even_allday_yn").prop('checked', true);
    $( "#even_allday_yn").prop('checked', false);

Dude try below code :

$("div.row-form input[type='checkbox']").attr('checked','checked')


$("div.row-form #estado_cat").attr("checked","checked");


$("div.row-form #estado_cat").attr("checked",true);

"checked" attribute 'ticks' the checkbox as soon as it exists. So to check/uncheck a checkbox you have to set/unset the attribute.

For checking the box:

$('#myCheckbox').attr('checked', 'checked');

For unchecking the box:


For testing the checked status:

if ($('#myCheckbox').is(':checked'))

Hope it helps...


Since you are in a modal window (whether dynamic or in the page) you can use the following code to accomplish your goal: (I ran into the same problem on my site and this is how I fixed it)


<div class="content-container" style="text-align: right;">
    <input type="checkbox" id="QueryGroupCopyQueries">
    <label for="QueryGroupCopyQueries">Create Copies</label>                                                   


$.each(queriesToAddToGroup, function (index, query) {
    if (query.groupAddType === queriesGroupAddType.COPY) {

        // USE FIND against your dynamic window and PROP to set the value
        // if you are using JQUERY 1.6 or higher.
        $(kendoWindow).find("input#QueryGroupCopyQueries").prop("checked", true);


In the above "kendoWindow" is my window (mine is dynamic, but I also do this when appending to an element directly in the page). I am looping through an array of data ("queriesToAddToGroup") to see if any rows have an attribute of COPY. If so I want to turn on the checkbox within the window that sets that attribute when a user saves from this window.



will work.Make sure true and false are not inside quotes.