Comments at DigitallyCreated Blog (for blogs tagged: "Validation")

Source Code commented on "Deep Inside ASP.NET MVC 2 Model Metadata and Validation"

Source Code — Fri, 08 Jul 2011 18:45:10 GMT

I have a question, When I apply a validation attribute (which is having associated validator to it) twice on a property, for eg I have number1 which should be lesser than number2 and number3. so I apply something like below.
[LessThan("Number2",ErrorMessage=)]
[LessThan("Number3",ErrorMessage=)]
public int Number1

problem here is when it evaluates Number1 < Number3 to true, then it is not checking for Number1 <Number2, it assumes that validation for the whole field is passed. How can we ensure, we go through each validation (attribute rule) and make sure the correct Validation error is returned.

Daniel Chambers commented on "Deep Inside ASP.NET MVC 2 Model Metadata and Validation"

Daniel Chambers — Mon, 15 Nov 2010 15:42:59 GMT

Thanks for clearing that one up Brad. :)

Brad Wilson commented on "Deep Inside ASP.NET MVC 2 Model Metadata and Validation"

Brad Wilson — Mon, 15 Nov 2010 12:17:47 GMT

Regarding your peanut gallery comment:

Our validation system is designed to be very specific to MVC. The ControllerContext is present so that a validation library could be developed which used ambient information about the request in progress to make decisions about how validation will proceed. The fact that we don't currently use that information ourselves is irrelevant, as this is an extensibility point in the system that's designed to be consumed by others.

If you are limiting yourself to DataAnnotations attributes and you want to consume them yourself from the business layer, I would suggest you use the DataAnnotations APIs yourself. In particular, you are looking for the static Validator class in System.ComponentModel.DataAnnotations.dll in .NET 4.

Thanigainathan commented on "Deep Inside ASP.NET MVC 2 Model Metadata and Validation"

Thanigainathan — Sun, 23 May 2010 16:55:07 GMT

Hi,

Your article is really very good. But its really surprising why Microsoft doesn't provide any documents on inner workings of MVC framework. Is that because its maintained in Codeplex ?

Please write a book on MVC which will be helpful for us .

Thanks,
Thani

Troy Cox commented on "Deep Inside ASP.NET MVC 2 Model Metadata and Validation"

Troy Cox — Mon, 10 May 2010 00:17:37 GMT

Nice post.

@ERolnkcki, I don't, for one, like my business models ever making it to the UI. I use view models. My view models use the validation.

--by the way Readability fixes your site so I can read it.

E Rolnicki commented on "Deep Inside ASP.NET MVC 2 Model Metadata and Validation"

E Rolnicki — Thu, 06 May 2010 13:17:38 GMT

good post. since you are validating your model in the business layer (as you should), just override the default model binder's OnModelUpdated to remove the validation on binding.