Determining if a .NET type is dynamic (created using Reflection.Emit)

Question

While the .NET 4 framework provides the Assembly.IsDynamic method, that's not the case with .NET 2.0/3.5.

The use case is simple: for logging purposes, I want to determine the underlying type name of an entity that might be wrapped by a dynamic proxy without having any references to NHibernate or Castle (which know about the proxy)

For example, I might have a CatProxYadaYada, but I'm interested in Cat.

What's the easiest way to get that type? I was thinking of this skeleton:

var type = obj.GetType();
while (IsProxy_Dynamic_Whatever(obj))
  type = type.BaseType;
return type;

Answer 1

If the assembly was generated using Emit, then you should be able to verify this by checking if the type's assembly is an AssemblyBuilder. In other words, something like this:

static Type GetNonEmittedType(Type t)
{
    if (t.Assembly is AssemblyBuilder)
        return GetNonEmittedType(t.BaseType);
    return t;
}

This might not work for every kind of dynamic proxy - it really depends on how it was generated. But it works with Emit.