javascript - jquery if checkbox is checked, alert with result isn't working - Stack Overflow

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I can't figure out what's wrong with this code. It is supposed to check if a checkbox is checked, and alert "checked" if it is and "not checked" if it's not. However it keeps returning the "checked" result every time.

$(document).ready(function () {
        $('#midmenusubmit').click(function () {
            if ($('input:c2:checked').val() != undefined) {
                alert("checked");
                //checked
            }
            else {
                alert("not checked");
                //not checked
            }

        });
    });


<input type="checkbox" id="c2" name="c2" ></input>


<img src="image.png" id="midmenusubmit" />

I can't figure out what's wrong with this code. It is supposed to check if a checkbox is checked, and alert "checked" if it is and "not checked" if it's not. However it keeps returning the "checked" result every time.

$(document).ready(function () {
        $('#midmenusubmit').click(function () {
            if ($('input:c2:checked').val() != undefined) {
                alert("checked");
                //checked
            }
            else {
                alert("not checked");
                //not checked
            }

        });
    });


<input type="checkbox" id="c2" name="c2" ></input>


<img src="image.png" id="midmenusubmit" />

• javascript
• jquery
• css

Share Improve this question Follow edited Mar 21, 2011 at 20:27 BoltClock 725k165165 gold badges1.4k1.4k silver badges1.4k1.4k bronze badges asked Mar 21, 2011 at 20:24 korbenkorben 53711 gold badge77 silver badges1818 bronze badges 1

• Your selector is wrong, it should be #c2 not :c2. – BoltClock Commented Mar 21, 2011 at 20:27

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2 Answers 2

Sorted by: Reset to default 5

Here's a more succinct way to check the state of your checkbox:

if ($('input#c2').is(':checked')) {

Better to use

$('input:c2:checked').length > 0

or

$('input:c2').is(':checked') // returns true or false

The .val() is looking for a value on the input element and never finds it hence it always being undefined

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