Question

I want to be able to hide an entire container when I check a checkbox.

* HTML *

<div class="showIt">
    <div>abc</div>
    <div>123</div>
    <div><input type="checkbox" /></div>
</div>

* CSS *

div.showIt {
    display:inherit;
}
div.hideIt {
    display:none;
}

* JavaScript (it does not work) *

<script>
jQuery.support.cors = true; // needed for ajax to work in certain older browsers and versions

$(document).ready(function(){

    $(this).change(function(e) {

        $(this).parent().toggleClass('showIt hideIt');

        $(this).closest("div").toggleClass('showIt hideIt');

    });

}); // end .ready()
</script>

Answer 1

You are syntactically wrong.

$(this) on your code does not select any element at that time.

$("input:checkbox").change(function(e) {
// ^ This here tell to select an input element of type `checkbox` and then attach an event to it
    $(this).parent().toggleClass('hideIt'); 
    //               ^ Here provide show those classes which you want to toggle, giving multiple class does not toggle between them

    $(this).closest("div").toggleClass('hideIt');
    //This is does same thing as above statement

});

---

You do not neeed

div.showIt {
    display:inherit;
}

Only toggle the .hideIt It is more than enough

Demo