using System;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;
using System.Reflection.Emit;
using System.Text;

namespace Demo {
    class Program {

        static void Main(string[] args) {
            Create();
        }

        public static void Create() {
            AssemblyName name = new AssemblyName("Com.DiQiSoft.Demo");
            AssemblyBuilder assembly = AppDomain.CurrentDomain.DefineDynamicAssembly(name, System.Reflection.Emit.AssemblyBuilderAccess.RunAndSave);
            ModuleBuilder module = assembly.DefineDynamicModule(name.Name, name.Name + ".dll");
            TypeBuilder typeOfExpress = module.DefineType("Express", TypeAttributes.Class | TypeAttributes.Public | TypeAttributes.AnsiClass | TypeAttributes.BeforeFieldInit);
            typeOfExpress.SetParent(typeof(object));
            var creator = typeof(Creator<>);
            var typeOfCreator = creator.MakeGenericType(typeOfExpress);
            var getMethod = typeOfExpress.DefineMethod("get_New", MethodAttributes.Public | MethodAttributes.HideBySig | MethodAttributes.SpecialName, typeOfCreator, Type.EmptyTypes);
            var property = typeOfExpress.DefineProperty("New", PropertyAttributes.HasDefault, typeOfCreator, Type.EmptyTypes);
            var generator = getMethod.GetILGenerator();
            var createMethod = typeOfCreator.GetMethod("Create");
            var local = generator.DeclareLocal(typeOfCreator);
            generator.Emit(OpCodes.Nop);
            generator.Emit(OpCodes.Call, createMethod);
            generator.Emit(OpCodes.Stloc_0);
            var lb = generator.DefineLabel();
            generator.Emit(OpCodes.Br_S, lb);
            generator.MarkLabel(lb);
            generator.Emit(OpCodes.Ldloc_0);
            generator.Emit(OpCodes.Ret);
            property.SetGetMethod(getMethod);
            typeOfExpress.CreateType();
            assembly.Save(name.Name + ".dll");
        }
    }

    public class Creator<T> {
        public static Creator<T> Create() {
            return new Creator<T>();
        }
    }
}