using System;
using System.Runtime.Remoting.Messaging;
using System.Runtime.Remoting.Proxies;

namespace TestRealProxy
{
    internal class Program
    {
        private static void Main(string[] args)
        {
            var service = new MyRealProxy().GetTransparentProxy() as IInterface;

            // 正确的结果
            var right = service.GetById(4);

            // 错误的结果
            Func<int, MyClass> func = service.GetById;
            var error = func(3);
        }
    }

    public interface IInterface<T> where T : class
    {
        T GetById(int id);
    }

    public interface IInterface : IInterface<MyClass>
    {
    }

    public class MyClass
    {
        public int Id { get; set; }
    }

    public class MyRealProxy : RealProxy
    {
        public MyRealProxy()
            : base(typeof(IInterface))
        {
        }

        public override IMessage Invoke(IMessage msg)
        {
            IMethodCallMessage methodCall = (IMethodCallMessage)msg;

            IMethodReturnMessage methodReturn = null;
            object[] copiedArgs = Array.CreateInstance(typeof(object), methodCall.Args.Length) as object[];
            methodCall.Args.CopyTo(copiedArgs, 0);
            try
            {
                object returnValue = new MyClass { Id = (int)methodCall.Args[0] };
                methodReturn = new ReturnMessage(returnValue, copiedArgs, copiedArgs.Length, methodCall.LogicalCallContext, methodCall);
            }
            catch (Exception ex)
            {
                methodReturn = new ReturnMessage(ex, methodCall);
            }

            return methodReturn;
        }
    }
}