Can Attributes target a specific field of an object field?

Question

Attributes provide the field attribute target. This however only seems to help when targeting the backing field of an auto-property.

If I add an attribute to a specific object field, the type of the field is known at compile time. Is there a way to target that attribute at fields on that type?

Example:

// class in my code
public class Foo
{
    [field: SomeAttribute] // <-- this should target TargetClass.TargetField, is it possible and how?
    public Bar TargetClass;
    
}

// class that might be defined in a library or part of code that I cannot edit or add attributes to
public class Bar
{
    public int TargetField;
}

I've looked through the Attribute documentation, but can't find anything related to this particular usecase. This leads me to think it's not directly supported.

However, intuitively I would think the compiler has all the information necessary to make this kind of targeting possible so maybe this is something that has been suggested but isn't implemented yet?

Answer 1

That's not a thing you can do. The attribute would need to be on the actual type/member intended. There is a concept of runtime properties in the "descriptor" model (rather than the reflection model) which would allow more flexibility, but that only applies in niche scenarios, so honestly: it isn't worth trying to explain.