Question

I need to create a proxy which intercepts properties in a class. I know how to create a dynamic proxy with Emit from an interface, but what if I don’t have an interface? I’ve seen samples which use RealProxy (like this one: Is there a way to call a method when any property of a class is set?) but is it possible to use type generation and emit to achieve the same thing? I don’t want the “owner” of the concrete class to see any traces of MarshalByRefObject if possible (see below)…

I believe Castle is able to do this, but maybe it’s using RealProxy under the covers?

User user = Create<User>();

public class User
{
    public string Name { get; set; } 
}

public T Create<T>()
{
    //magic happens here... :)
    return (T)GenerateInterceptingProxyFromT(typeof(T));
}

Answer 1

I just started messing with postshrp, one of the AOP tools Miguel mentioned, do functionally what you are trying to do. It uses “static weaving” to inject code at compile time so should be invisible to consumers. Obviously, you need to modify the code that you want to instrument for this to work.
The answer to This question suggests using the profiler API which may be an option for you if PostSharp, or Castle won’t do what you need.