http://stackoverflow.com/questions/3260748/default-resource-for-data-annotations-in-asp-net-mvc
Add this class somewhere in your project:
public class ExternalResourceDataAnnotationsValidator : DataAnnotationsModelValidator<ValidationAttribute> { /// <summary> /// The type of the resource which holds the error messqages /// </summary> public static Type ResourceType { get; set; } /// <summary> /// Function to get the ErrorMessageResourceName from the Attribute /// </summary> public static Func<ValidationAttribute, string> ResourceNameFunc { get { return _resourceNameFunc; } set { _resourceNameFunc = value; } } private static Func<ValidationAttribute, string> _resourceNameFunc = attr => attr.GetType().Name; public ExternalResourceDataAnnotationsValidator(ModelMetadata metadata, ControllerContext context, ValidationAttribute attribute) : base(metadata, context, attribute) { if (Attribute.ErrorMessageResourceType == null) { this.Attribute.ErrorMessageResourceType = ResourceType; } if (Attribute.ErrorMessageResourceName == null) { this.Attribute.ErrorMessageResourceName = ResourceNameFunc(this.Attribute); } } }
and in your global.asax, add the following:
// Add once ExternalResourceDataAnnotationsValidator.ResourceType = typeof(CustomDataAnnotationsResources); // Add one line for every attribute you want their ErrorMessageResourceType replaced. DataAnnotationsModelValidatorProvider.RegisterAdapter(typeof(RangeAttribute), typeof(ExternalResourceDataAnnotationsValidator));
It will look for a property with the same name as the validator type for the error message. You can change that via the ResourceNameFunc property.
EDIT: AFAIK this works from MVC2 onwards, as DataAnnotationsModelValidatorProvider was introduced in MVC2.
To achieve this, I created a new class that inherits from RequiredAttribute, and the error message is embedded inside this new class:
The error message is taken from the ValidationResource.resx file, where I list the error message as follows:
public class RequiredWithMessageAttribute : RequiredAttribute { public RequiredWithMessageAttribute() { ErrorMessageResourceType = typeof(ValidationResource); ErrorMessageResourceName = "RequiredErrorMessage"; } }
RequiredErrorMessage --> "{0} is required."
where {0} = display name.
I then annotate my models like this, so I never have to repeat my error message declarations:
[RequiredWithMessage] public string Name { get; set; }
Once you do this, an error message ("Name is required.") will appear whenever validation fails.
This works properly with ASP.NET MVC's server-side validation and client-side validation.