I currently migrated my project to MVC 2 and IDataErrorInfo doesn't seem to work when using default model binding and validation. Is it cut out?
It's certainly in MVC 2 Preview 2. Look at DefaultModelBinder.OnPropertyValidating
and OnModelUpdated
.
SUMMARY
I posted this error to MVC 2 issue tracker: http://aspnet.codeplex.com/WorkItem/View.aspx?WorkItemId=4891
It will be resolved in next preview release.
DefaultModelBinder in MVC 1.0:
protected virtual void OnPropertyValidated(ControllerContext controllerContext, ModelBindingContext bindingContext, PropertyDescriptor propertyDescriptor, object value)
{
IDataErrorInfo model = bindingContext.Model as IDataErrorInfo;
if (model != null)
{
string str = model[propertyDescriptor.Name];
if (!string.IsNullOrEmpty(str))
{
string key = CreateSubPropertyName(bindingContext.ModelName, propertyDescriptor.Name);
bindingContext.ModelState.AddModelError(key, str);
}
}
}
DefaultModelBinder in MVC 2.0 beta:
protected virtual void OnPropertyValidated(ControllerContext controllerContext, ModelBindingContext bindingContext, PropertyDescriptor propertyDescriptor, object value)
{
ModelMetadata metadata = bindingContext.PropertyMetadata[propertyDescriptor.Name];
metadata.Model = value;
string prefix = CreateSubPropertyName(bindingContext.ModelName, metadata.PropertyName);
foreach (ModelValidator validator in metadata.GetValidators(controllerContext))
{
foreach (ModelValidationResult result in validator.Validate(bindingContext.Model))
{
bindingContext.ModelState.AddModelError(CreateSubPropertyName(prefix, result.MemberName), result.Message);
}
}
if ((bindingContext.ModelState.IsValidField(prefix) && (value == null)) && !TypeHelpers.TypeAllowsNullValue(propertyDescriptor.PropertyType))
{
bindingContext.ModelState.AddModelError(prefix, GetValueRequiredResource(controllerContext));
}
}
It doesn't use IDataErrorInfo this[string columnName] property... Seems like a bug, because DefaultModelBinder still uses Error property. It is inconsistency at least.
EDIT
I used reflector and noticed that DataErrorInfoPropertyModelValidator doesn't seem to be used, so I created my own class:
public class DataErrorInfoModelPropertyValidatorProvider : ModelValidatorProvider
{
// Methods
public override IEnumerable<ModelValidator> GetValidators(ModelMetadata metadata, ControllerContext context)
{
if (metadata == null)
{
throw new ArgumentNullException("metadata");
}
if (context == null)
{
throw new ArgumentNullException("context");
}
var validators = new List<ModelValidator>();
validators.Add(new DataErrorInfoPropertyModelValidator(metadata, context));
return validators;
}
internal sealed class DataErrorInfoPropertyModelValidator : ModelValidator
{
// Methods
public DataErrorInfoPropertyModelValidator(ModelMetadata metadata, ControllerContext controllerContext)
: base(metadata, controllerContext)
{
}
public override IEnumerable<ModelValidationResult> Validate(object container)
{
if (container != null)
{
IDataErrorInfo info = container as IDataErrorInfo;
if (info != null)
{
string str = info[Metadata.PropertyName];
if (!string.IsNullOrEmpty(str))
{
ModelValidationResult[] resultArray = new ModelValidationResult[1];
ModelValidationResult result = new ModelValidationResult();
result.Message = str;
resultArray[0] = result;
return resultArray;
}
}
}
return Enumerable.Empty<ModelValidationResult>();
}
}
}
Then I used:
ModelValidatorProviders.Providers.Add(new DataErrorInfoModelPropertyValidatorProvider());
And it works:) This is just temporary solution. Will have to be corrected in final MVC 2.
EDIT
I also changed if (base.Metadata.Model != null)
to if (container != null) in Validate()
method of DataErrorInfoPropertyModelValidator
.