How do I manually trigger validation on a MVC form?

How do I manually trigger validation on a MVC form?

I have a dropdown list on my page that I want the change event to trigger
validation on either the whole form or a specific field on the form. My
Jquery:
$(function () {
$("#MyDDL").change(function () {
$("#MyForm").validate());
});
});
I know the change function is being called, tested it with an alert.