TypeLoadException: Type 'Castle.Proxies.IComponentProxy' from assembly 'DynamicProxyGenAssembly2' is attempting to implement an inaccessible interface

Question

I would like to log the calling of user interface methods.

My idea is to intercept the MyUserInterface class which inherits from System.Windows.Forms.Form.

However, I got TypeLoadException: Type 'Castle.Proxies.IComponentProxy' from assembly 'DynamicProxyGenAssembly2' is attempting to implement an inaccessible interface

How to solve this issue?

Am I missing something on registration?

Thank you!

I also save the code on fiddle. You can try to run.

using System;
using Autofac;
using Autofac.Extras.DynamicProxy;
using Castle.DynamicProxy;
public class Program
{
    public static void Main()
    {
        ContainerBuilder builder = new ContainerBuilder();      
        builder.RegisterType<MyInterceptor>();
        builder.RegisterType<MyUserInterface>().As<IMyUserInteraface>()
            .EnableInterfaceInterceptors()
            .InterceptedBy(typeof(MyInterceptor));          

        var container = builder.Build();
        var ui = container.Resolve<IMyUserInteraface>();
        ui.Show();
    }       
}
public class MyInterceptor : IInterceptor
{
    public void Intercept(IInvocation invocation)
    {
        Console.WriteLine("UI intercepted and logged");
        invocation.Proceed();
    }
}
//If MyUserInterface inherit Form, will get TypeLoadException.
//TypeLoadException: Type 'Castle.Proxies.IComponentProxy' from assembly 'DynamicProxyGenAssembly2, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null' is attempting to implement an inaccessible interface.
//public class MyUserInterface : Form, IMyUserInteraface
public class MyUserInterface : IMyUserInteraface
{
    public void Show()
    {
        Console.WriteLine("Show something");
    }
}
public interface IMyUserInteraface
{
    void Show();
}

I had tried to remove inheritance Form. Then it works. But MyUserInterface have to inherit from Form.

Answer 1

Code here

For now, solved by using CreateInterfaceProxyWithTarget in ProxyGenerator.

using System;
using Autofac;
using Autofac.Extras.DynamicProxy;
using Castle.DynamicProxy;
using System.Windows.Forms;

public class Program
{
    public static void Main()
    {
        var builder = new ContainerBuilder();
        //builder.RegisterType<MyInterceptor>();
        //builder.RegisterType<MyUserInterface>().As<IMyUserInteraface>()
        //    .EnableInterfaceInterceptors()
        //    .InterceptedBy(typeof(MyInterceptor));

        var generator = new ProxyGenerator();
        var myUserInterface = new MyUserInterface();
        var userInterfaceProxy = generator.CreateInterfaceProxyWithTarget<IMyUserInteraface>(myUserInterface, new MyInterceptor());

        builder.RegisterInstance(userInterfaceProxy).As<IMyUserInteraface>();

        var container = builder.Build();
        var ui = container.Resolve<IMyUserInteraface>();
        ui.Run();
    }
}
public class MyInterceptor : IInterceptor
{
    public void Intercept(IInvocation invocation)
    {
        Console.WriteLine("UI intercepted and logged");
        invocation.Proceed();
    }
}

public class MyUserInterface : Form, IMyUserInteraface
{
    public void Run()
    {
        Console.WriteLine("Show something");
    }
}
public interface IMyUserInteraface
{
    void Run();
}