How to calling a function in a .net dll through an interface loaded through reflection.

Question

Hello I'll try my best to explain this.

Basically, I am loading a library through reflection using the Assembly.LoadFile.

From there I have an interface IFace that defines a method "GetStrings" that returns an array of strings.

The dynamically loaded DLL has a class named "Class1" that implements IFace.

I need a way to call this interfaced method through the dynamically loaded lib. I'd like to keep it tightly coupled, which leaves me wondering what to do. I know I can use MethodInvoker to call the method, but I'm trying to find a way I can do something like this:

IFace obj = (IFace)ReflectionAssembly.Class1;
string[] strs = obj.GetStrings();

Any ideas?

Answer 1

Once you have the Type via Reflection (using something like Assembly.GetType), you can use Activator.CreateInstance:

IFace obj = (IFace)Activator.CreateInstance(class1Type);
string[] strs = obj.GetStrings();

Answer 2

Something like:

    var assm = Assembly.Load("ClassLibrary1");
    var type = assm.GetType("ClassLibrary1.Class1");
    var instance = Activator.CreateInstance(type) as IFace;
    string[] strings = instance.GetStrings();

Answer 3

Use Assembly.CreateInstance() to create the object, pass it a 'well known name'. Cast the return value to IFace, the rest is easy. Oh, don't use LoadFile, use LoadFrom.