ASP.NET MVC: Is Data Annotation Validation Enough?

Question

I\'m using the Data Annotation validation extensively in ASP.NET MVC 2. This new feature has been a huge time saver, as I\'m now able to define both client-side validation

Answer 1

The DataAnnotation is certainly not enough. I use it extensively also to pre-validate my calls to the domain model to get better error reporting and fail as early as possible.

You can however tweak the DataAnnotation Model yourself to ensure properties with [Required] MUST be posted. (will follow up with code later today).

UPDATE Get the source for DataAnnotations Model Binder and find this line in DataAnnotationsModelBinder.cs

// Only bind properties that are part of the request
if (bindingContext.ValueProvider.DoesAnyKeyHavePrefix(fullPropertyKey)) {

Change it to

// Only bind properties that are part of the request
bool contextHasKey = bindingContext.ValueProvider.DoesAnyKeyHavePrefix(fullPropertyKey);
bool isRequired = GetValidationAttributes(propertyDescriptor).OfType().Count() > 0;
if (contextHasKey || (!contextHasKey && isRequired)) {