html if - How to check whether a checkbox is checked in jQuery?




not onclick (25)

Use jQuery's is() function:

if($("#isAgeSelected").is(':checked'))
    $("#txtAge").show();  // checked
else
    $("#txtAge").hide();  // unchecked

I need to check the checked property of a checkbox and perform an action based on the checked property using jQuery.

For example, if the age checkbox is checked, then I need to show a textbox to enter age, else hide the textbox.

But the following code returns false by default:

if ($('#isAgeSelected').attr('checked'))
{
    $("#txtAge").show();
}
else
{
    $("#txtAge").hide();
}

How do I successfully query the checked property?


The top answer didn't do it for me. This did though:

<script type="text/javascript">
    $(document).ready(function(){

        $("#li_13").click(function(){
            if($("#agree").attr('checked')){
                $("#saveForm").fadeIn();
            }
            else
            {
                $("#saveForm").fadeOut();
            }
        });
    });
</script>

Basically when the element #li_13 is clicked, it checks if the element # agree (which is the checkbox) is checked by using the .attr('checked') function. If it is then fadeIn the #saveForm element, and if not fadeOut the saveForm element.


jQuery 1.6+

$('#isAgeSelected').prop('checked')

jQuery 1.5 and below

$('#isAgeSelected').attr('checked')

Any version of jQuery

// Assuming an event handler on a checkbox
if (this.checked)

All credit goes to Xian.


Since jQuery 1.6, the behavior of jQuery.attr() has changed and users are encouraged not to use it to retrieve an element's checked state. Instead, you should use jQuery.prop():

$("#txtAge").toggle(
    $("#isAgeSelected").prop("checked") // For checked attribute it returns true/false;
                                        // Return value changes with checkbox state
);

Two other possibilities are:

$("#txtAge").get(0).checked
$("#txtAge").is(":checked")

I am using this and this is working absolutely fine:

$("#checkkBoxId").attr("checked") ? alert("Checked") : alert("Unchecked");

Note: If the checkbox is checked it will return true otherwise undefined, so better check for the "TRUE" value.


if($("#checkkBoxId").is(':checked')){
  alert("Checked=true");
}

or

if($("#checkkBoxId").attr('checked') == true){
  alert("checked=true");
}

Though you have proposed a JavaScript solution for your problem (displaying a textbox when a checkbox is checked), this problem could be solved just by css. With this approach, your form works for users who have disabled JavaScript.

Assuming that you have the following HTML:

<label for="show_textbox">Show Textbox</label>
<input id="show_textbox" type="checkbox" />
<input type="text" />

You can use the following CSS to achieve the desired functionality:

 #show_textbox:not(:checked) + input[type=text] {display:none;}

For other scenarios, you may think of appropriate CSS selectors.

Here is a Fiddle to demonstrate this approach.


I think it will be the simple one

$('#isAgeSelected').change(function() {
    if($(this).is(":checked")) {
        $('#txtAge').show();
    }
else{
        $('#txtAge').hide();
    }                                          
});

Toggle: 0/1 or else

<input type="checkbox" id="nolunch" />
<input id="checklunch />"

    $('#nolunch').change(function () {
    if ($(this).is(':checked')) {
        $('#checklunch').val('1');
    };
    if ($(this).is(':checked') == false) {
        $('#checklunch').val('0');
    };
});

This worked for me:

$get("isAgeSelected ").checked == true

Where isAgeSelected is the id of the control.

Also, @karim79's answer works fine. I am not sure what I missed at the time I tested it.

Note, this is answer uses Microsoft Ajax, not jQuery


Use:

<input type="checkbox" name="planned_checked" checked id="planned_checked"> Planned

$("#planned_checked").change(function() {
    if($(this).prop('checked')) {
        alert("Checked Box Selected");
    } else {
        alert("Checked Box deselect");
    }
});

    $("#planned_checked").change(function() {
        if($(this).prop('checked')) {
            alert("Checked Box Selected");
        } else {
            alert("Checked Box deselect");
        }
    });
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<input type="checkbox" name="planned_checked" checked id="planned_checked"> Planned

I am using this:

 <input type="checkbox" id="isAgeSelected" value="1" /> <br/>
 <input type="textbox" id="txtAge" />

 $("#isAgeSelected").is(':checked') ? $("#txtAge").show() : $("#txtAge").hide();

Use this:

if ($('input[name="salary_in.Basic"]:checked').length > 0)

The length is greater than zero if the checkbox is checked.


This example is for button.

Try the following:

<input type="button" class="check" id="checkall" value="Check All" />  &nbsp; <input type="button" id="remove" value="Delete" /> <br/>

<input type="checkbox" class="cb-element"  value="1" /> Checkbox  1 <br/>
<input type="checkbox" class="cb-element"  value="2" /> Checkbox  2 <br/>
<input type="checkbox" class="cb-element"  value="3" /> Checkbox  3 <br/>


$('#remove').attr('disabled', 'disabled'); 

$(document).ready(function() {  

    $('.cb-element').click(function() {

        if($(this).prop('checked'))
        {
            $('#remove').attr('disabled', false);
        }
        else
        {
            $('#remove').attr('disabled', true);
        }
    });   

    $('.check:button').click(function()
{
    var checked = !$(this).data('checked');
    $('input:checkbox').prop('checked', checked);
    $(this).data('checked', checked);

    if(checked == true)
    {
        $(this).val('Uncheck All');
         $('#remove').attr('disabled', false);
    }

    else if(checked == false)
    {
        $(this).val('Check All');
        $('#remove').attr('disabled', true);
    }
});
});

You can use:

  if(document.getElementById('isAgeSelected').checked)
    $("#txtAge").show();  
  else
    $("#txtAge").hide();

if($("#isAgeSelected").is(':checked'))
  $("#txtAge").show();  
else
  $("#txtAge").hide();

Both of them should work.


My way of doing this is:

if ( $("#checkbox:checked").length ) {       
    alert("checkbox is checked");
} else {
    alert("checkbox is not checked");
}

This is some different method to do the same thing:

$(document).ready(function (){

    $('#isAgeSelected').click(function() {
        // $("#txtAge").toggle(this.checked);

        // Using a pure CSS selector
        if ($(this.checked)) {
            alert('on check 1');
        };

        // Using jQuery's is() method
        if ($(this).is(':checked')) {
            alert('on checked 2');
        };

        //  // Using jQuery's filter() method
        if ($(this).filter(':checked')) {
            alert('on checked 3');
        };
    });
});
<script src="http://code.jquery.com/jquery-1.9.1.js"></script>
<input type="checkbox" id="isAgeSelected"/>
<div id="txtAge" style="display:none">Age is something</div>

$(document).ready(function() {    
    $('#agecheckbox').click(function() {
        if($(this).is(":checked"))
        {
            $('#agetextbox').show();
        } else {
            $('#agetextbox').hide();
        }
    });
});

If you are using an updated version of jquery, you must go for .prop method to resolve your issue:

$('#isAgeSelected').prop('checked') will return true if checked and false if unchecked. I confirmed it and I came across this issue earlier. $('#isAgeSelected').attr('checked') and $('#isAgeSelected').is('checked') is returning undefined which is not a worthy answer for the situation. So do as given below.

if($('#isAgeSelected').prop('checked')) {
    $("#txtAge").show();
} else {
    $("#txtAge").hide();
}

Hope it helps :)- Thanks.


How do I successfully query the checked property?

The checked property of a checkbox DOM element will give you the checked state of the element.

Given your existing code, you could therefore do this:

if(document.getElementById('isAgeSelected').checked) {
    $("#txtAge").show();
} else {
    $("#txtAge").hide();
}

However, there's a much prettier way to do this, using toggle:

$('#isAgeSelected').click(function() {
    $("#txtAge").toggle(this.checked);
});
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<input type="checkbox" id="isAgeSelected"/>
<div id="txtAge" style="display:none">Age is something</div>

There are many ways to check if a checkbox is checked or not:

Way to check using jQuery

if (elem.checked)
if ($(elem).prop("checked"))
if ($(elem).is(":checked"))
if ($(elem).attr('checked'))

Check example or also document:


$(selector).attr('checked') !== undefined

This returns true if the input is checked and false if it is not.


Using jQuery > 1.6

<input type="checkbox" value="1" name="checkMeOut" id="checkMeOut" checked="checked" />

// traditional attr
$('#checkMeOut').attr('checked'); // "checked"
// new property method
$('#checkMeOut').prop('checked'); // true

Using the new property method:

if($('#checkMeOut').prop('checked')) {
    // something when checked
} else {
    // something else when not
}

This works for me:

/* isAgeSelected being id for checkbox */

$("#isAgeSelected").click(function(){
  $(this).is(':checked') ? $("#txtAge").show() : $("#txtAge").hide();
});

It's pretty crazy town that the only way to make checked false is to omit any values. With Angular 1.x, you can do this:

  <input type="radio" ng-checked="false">

which is a lot more sane, if you need to make it unchecked.







jquery html dom checkbox