If you only want a user to be able to select a limited number of options in a checkbox set, you can use this simple hack.
Please note, because this is a JavaScript modification it only works on the client side. This check isn't implemented in the server side validation, but since the aim is to prevent human error I think it's safe to assume that JavaScript can do the job.
In this example, a checkbox set with the name obj_10 is only allowed to have two checkboxes selected. You will need to edit the code to suit your form. If you want to apply limits to more than one checkbox set, duplicate and amend this code accordingly.
Open sc_admin/js/forms.js
Add the following code to the validateContact() function, after the section for checkboxes:
// ONLY ALLOW TWO OPTIONS FOR OBJ_10
if ($("input[name='obj_10[]']:checked").length > 2) {
var mylist = $("#obj_10_1").parents("ul")[0];
$(mylist).after("<p class=\"err\"><em>Please only select two options</em></p>");
}
Users will now see an error message if they exceed the allowed number of options in the checkbox set.
