This demo shows how you can validate form editors when using ASP.NET MVC controls. Form editors extract validation rules from data annotations attributes to the fields of the model (see the EditorsViewModel.cs file). Custom data annotations are supported as well (AgeVerification in this demo).
Note that the "Register" button here does not implement the usual onClick event handler. Instead, it has the useSubmitBehavior property set to true. This setting tells the button to validate and submit the HTML form in which it is nested, with no further configuration required.