Question

I want to create a Model:

public class TestModel
{
    Microdata(Data = "data-test=this is a test!")]
    public bool Test { get; set; }
}

Then in the view:

@Html.DisplayForModel()

The result i’m looking for is something like this:

<label>Test:</label> <input type="checkbox" data-test="this is a test!" />

I’ve already created a custom attribute class, but this didn’t produce anything.

[AttributeUsage(AttributeTargets.Property | AttributeTargets.Class, AllowMultiple = false, Inherited = true)]
public class MicrodataAttribute : Attribute
{
    public string Data { get; set; }

    public RouteValueDictionary GetAttributes()
    {
        var attributes = new RouteValueDictionary();

        if (this.Data != null)
        {
            string[] kv = this.Data.Split(',');
            attributes.Add(kv[0], kv[1]);
        }
        return attributes;
    }
}



public class MetadataProvider : DataAnnotationsModelMetadataProvider
{
    protected override ModelMetadata CreateMetadata(IEnumerable<Attribute> attributes, Type containerType, Func<object> modelAccessor, Type modelType, string propertyName)
    {
        var metadata = base.CreateMetadata(attributes, containerType, modelAccessor, modelType, propertyName);
        var additionalValues = attributes.OfType<HtmlPropertiesAttribute>().FirstOrDefault();
        if (additionalValues != null)
        {
            metadata.AdditionalValues.Add("HtmlAttributes", additionalValues);
        }
        return metadata;
    }
}

Answer 1

Why would it? There’s no code that uses your attribute…

Read the blog post below – it describes how MVC uses metadata and has an example of a custom object template you will need to write:

http://bradwilson.typepad.com/blog/2009/10/aspnet-mvc-2-templates-part-1-introduction.html