I am trying to choose one of the validation frameworks for a major application, and while both options seem enticing, I was wondering whether there are any specific pros and cons I should be aware of before committing to one or the other.
Validation with attributes is not best solution in my view. Firstly you have to reference infrastructure in domain model. Secondly you don't have any chance to add validation to compiled classes. Lastly you can't validate complex logic with attributes and you have to make Validate method to entity and that just seems awkward.
In my opinion validation should be separated to different object. For example IValidator where you could define validation as rules. Using framework like xVal helps to do validation in presentation layer with JavaScript.
You may want to look for xVal and FluentValidation for .NET. NHibernate Validator 1.2 alpha has fluent syntax as well and it is integrated with xVal (not sure about alpha, but 1.0 should be).
Enterprise Validation Block has few negative sides as well. My entity's properties ended up having 3 rows of attributes and made readability worse. Trying to add validation with AND or OR operators is quite painful too.
One thing that I have found with the Enterprise Library blocks is that it can force you to use other blocks that you don't want/need. For instance, the Validation one might use the logging block, but you were happy with your own logging system. now your app logs things in different ways. That said, I have liked the look of the Validation block in the Ent Lib. I have not played with Spring.NET tho.
来源：https://stackoverflow.com/questions/751700/which-validation-framework-to-choose-spring-validation-or-validation-applicatio