Submit empty checkbox

script.js

/* Add before submit action to fix checkbox issue
Change value to "off" for not-checked checkboxes and check them.
In this case value "off" (instead of original value) will be stored.
 */
 
    $('form#post').submit(function(e) {
        $('#some-wrapper input[type=checkbox]:not(:checked)').each(function(){
            var curItem=$(this);
            curItem.val('off');
            curItem.prop('checked', true);
        });
    })