PostSharp C# - How to Implement All Fields Required

Question

PostSharp contracts make it easy to label individual fields as Required. But I want a class attribute that makes all of the class fields required. I'm guessing I would have to implement a custom aspect to support this.

It seems like it would be a common need for anyone passing around data containers. Can anyone direct me to some code that implements a custom "AllFieldsRequired" aspect in PostSharp?

Answer 1

You can implement PostSharp.Aspects.IAspectProvider:

public class AllFieldsRequiredAttribute : TypeLevelAspect, IAspectProvider
{
    IEnumerable<AspectInstance> IAspectProvider.ProvideAspects(object targetElement)
    {
        Type type = (Type)targetElement;
        return type.GetFields().Select(
           m => new AspectInstance(m, new ObjectConstruction(typeof(RequiredAttribute))));
    }
}

[AllFieldsRequired]
public class Foo
{
    public string Bar;
    public object Baz;
}