This project provides common validation attributes (full list on the project website) which extend the built-in ASP.NET DataAnnotations (Required, Range, RegularExpression and StringLength).

The core library provides server-side validation attributes that can be used in any .NET 4.0 or 4.5 project (no MVC dependency). There is also an easily pluggable client-side validation library which can be used in ASP.NET MVC 3 or 5 projects using unobtrusive jquery validation (only MVC included javascript files are required).

All validation attributes are covered with unit tests and also have a dedicated controller in the included sample website (click Demos to see a demonstration of each validation attribute). 

Please see the project website for details: https://dataannotationsextensions.apphb.com/