Show/Hide with Checkbox using jQuery

Question

I am trying to have a section of an html form to show/hide based on a checkbox. This is the essence code I have:

<script src="/js/jquery.js"></script>
<script language="JavaScript">
    function toggle(className){
        var $input = $(this);
        if($(this).prop('checked'))
            $(className).show();
        else
            $(className).hide();
        }
</script>

<fieldset><legend>Check Here
    <input type="checkbox" onclick="toggle('.myClass')" ></legend>
    <span class="myClass">
        <p>This is the text.</p>
    </span>
</fieldset>

When you click on the checkbox, the span gets hidden and will not come back. I have also used $(this).is(':checked'). It appears that $(this).prop('checked') is evaluating to false whether it is checked or not. My best guess is that I am using $(this) incorrectly. What am I missing here?

Answer 1

HTML, pass this from on click event

<input type="checkbox" onclick="toggle('.myClass', this)" ></legend>

JS

function toggle(className, obj) {
    var $input = $(obj);
    if ($input.prop('checked')) $(className).hide();
    else $(className).show();
}

OR, without using prop you can just do:

function toggle(className, obj) {
    if ( obj.checked ) $(className).hide();
    else $(className).show();
}

OR, in one-line using .toggle( display ):

function toggle(className, obj) {
    $(className).toggle( !obj.checked )
}

Answer 2

Use an event handler that is'nt inline, and then just toggle() the element based on the checkbox state :

<script src="/js/jquery.js"></script>
<script type="text/javaScript">
    $(function() {
        $('input[type="checkbox"]').on('change', function() {
            $(this).closest('fieldset').find('.myClass').toggle(!this.checked);
        });
    });
</script>

<fieldset>
    <legend>Check Here<input type="checkbox"></legend>
    <span class="myClass">
        <p>This is the text.</p>
    </span>
</fieldset>

FIDDLE

This would even work with several fieldset's with the same markup.

Answer 3

try binding event via jQuery, and then you can access to $(this):

$(document).ready(function() {
  $(":checkbox").click(function(event) {
    if ($(this).is(":checked"))
      $(".myClass").show();
    else
      $(".myClass").hide();
  });
});