I've updated my Field Plug-in:
http://jquery.com/plugins/project/field
I've fixed an issue with the $.formHash() method and added the following:
$("input:checkbox").limitSelection(3, errorCallback, successCallback);
Limits the user from being able to select more than 3 items in a
checkbox/select element. If 3 items or less are selected, the
successCallback is executed. If more than 3 items is selected, the
errorCallback is executed.
The limitSelection() was inspired by a recent post on this board. It works
with checkbox and select elements (although the select implementation is far
from perfect.)
$("input:checkbox").createCheckboxRange();
The createCheckboxRange() allows you to create a Gmail-like checkbox range
selector. By clicking on a checkbox element and then [SHIFT] clicking on an
additional checkbox element, the entire range of checkbox elements between
the first and second elements clicked with be checked or unchecked (based
upon the status of the first checkbox clicked.)
-Dan
