Creating WCF service by determining type at runtime - wcf

Question

I am trying to create a WCF service without knowing its type/interface at runtime. To do this, I use ChannelFactory. ChannelFactory is a generic class so I need to use Type.MakeGenericType. The type I pass to MakeGenericType is from a list of interfaces I previously gathered with reflection by searching some assemblies.
Ultimately, I call MethodInfo.Invoke to create the object. The object is created just fine, but I cannot cast it to the proper interface. Upon casting, I receive the following error:
"Unable to cast transparent proxy to type 'Tssc.Services.MyType.IMyType'"
After some experimenting, I have found that the interface/type passed to MakeGenericType seems to be the problem. If I substitute the interface in my list with the actual interface, then everything works fine. I have combed through the two objects and cannot see a difference. When I modify the code to produce both types, comparing them with Equals returns false. It is unclear to me whether Equals is just checking that they are referring to the same object (not) or thety are checking all properties, etc.
Could this have something to do with how I gathered my interfaces (Reflection, saving in a list...)? A comparison of the objects seems to indicate they are equivalent. I printed all properties for both objects and they are the same. Do I need to dig deeper? If so, into where?
// createService() method
//*** tried both of these interfaces, only 2nd works - but they seem to be identical
//Type t = interfaces[i]; // get type from list created above - doesn't work
Type t = typeof(Tssc.Services.MyType.IMyType); // actual type - works OK
// create ChannelFactory type with my type parameter (t)
Type factoryType = typeof(ChannelFactory<>);
factoryType = factoryType.MakeGenericType(new Type[] { t });
// create ChannelFactory<> object with two-param ctor
BasicHttpBinding binding = new BasicHttpBinding();
string address = "blah blah blah";
var factory = Activator.CreateInstance(factoryType, new object[] { binding, address });
// get overload of ChannelFactory<>.CreateChannel with no parameters
MethodInfo method = factoryType.GetMethod("CreateChannel", new Type[] { });
return method.Invoke(factory, null);
//--------------- code that calls code above and uses its return
object ob = createService();
//*** this cast fails
Tssc.Services.MyType.IMyType service = (Tssc.Services.MyType.IMyType)ob;

Answer 1

Ok, I understand whats happening here - the problem is relating to loading the same assembly being effectively loaded twice - once via a reference, and once via the assembly load command. What you need to do is change the place where you load your assembly, and check to see if it already exists in the current AppDomain, like this maybe:
Assembly assembly = AppDomain.CurrentDomain.GetAssemblies().FirstOrDefault(a => a.GetName().Name.Equals("ClassLibrary1Name"));
if (assembly == null)
{
assembly = System.Reflection.Assembly.LoadFile("path to your assembly");
}
//do your work here
This way if the assembly is already loaded into memory, it'll use that one.