use jquery to insert hidden checkbox for unchecked check boxes

unchecked check box form submit in rails with jquery

The rails check_box form helper inserts a hidden checkbox to handle unchecked check boxes.  This doesn't work when the check box is within an array-like parameter - i.e. project[invoice_attributes][blah].

So - below will append a hidden form field with a value - so it can be handled in your controller or model etc.

for:
<%= check_box_tag("instance[data][blah]") %>

jquery:
  $("#instance_form").submit(function() {
    // insert hidden checkbox with value 0 - so unchecked checkboxes submit a value
    $('input:checkbox').not(':checked').each(function() {
        $("#instance_form").append("<input type='hidden' name='" + this.name + "' value='0' />");
    });
    return true;
  });

Thanks a lot

Thanks!