Uppercase attribute that converts the input to uppercase

Question

I am working in MVC4 and want to define a model using an Uppercase attribute. The idea would be that the presence of the Uppercase attribute would cause the mod

Answer 1

You're right, ValidationAttribute is not the right fit. It seems like doing this at the Model Binding stage would be a better idea. See this article for a detailed explanation of how to customize this behavior.

Based on the information provided there, I believe you should be able to create an attribute based on CustomModelBinderAttribute like this:

[AttributeUsage(AttributeTargets.Property)]
public class UppercaseAttribute : CustomModelBinderAttribute
{
    public override IModelBinder GetBinder()
    {
        return new UppercaseModelBinder();
    }

    private class UppercaseModelBinder : DefaultModelBinder
    {
        public override object BindModel(
            ControllerContext controllerContext,
            ModelBindingContext bindingContext)
        {
            var value = base.BindModel(controllerContext, bindingContext);
            var strValue = value as string;
            if (strValue == null)
                return value;
            return strValue.ToUpperInvariant();
        }
    }
}

I have not tested this. Let me know if it works or not.