In this post I´ll explain how to validate your custom attributes in the client side. There are two ways to do it, one is when your attribute is inheriting from RequiredAttribute, RegularExpressionAttribute, etc, and the other is when your custom attribute is completely new.
The jQuery validation and the jQuery unobtrusive validation are frameworks for client validation. The default implementation uses the en-US culture, that is, number in the format of dot deparating the decimal places and date in the format MM/dd/yyyy. In this post we will customize that according with the culture chosen by the user.