MSIL实用指南-生成内部类

生成内部类用TypeBuilder的DefineNestedType方法，得到另一个TypeBuilder。
内部类的可访问性都是TypeAttributes的“Nested”开头一些成员。
实例代码:
ypeBuilder nestedBuilder = typeBuilder.DefineNestedType("NestedClass", TypeAttributes.NestedPublic | TypeAttributes.Sealed);

完整程序如下：

using System;
using System.Reflection;
using System.Reflection.Emit;

namespace LX1_ILDemo
{
    class Demo27_NestedType
    {
        static string binaryName = "Demo27_NestedType.dll";
        static string namespaceName = "LX1_ILDemo";
        static string typeName = "DemoNestedType";

        static AssemblyBuilder assemblyBuilder;
        static ModuleBuilder moduleBuilder;
        static TypeBuilder typeBuilder;

        static void Emit_NestedMethod()
        {
            TypeBuilder nestedBuilder = typeBuilder.DefineNestedType("NestedClass", TypeAttributes.NestedPublic | TypeAttributes.Sealed);
            var testMethod = nestedBuilder.DefineMethod("Hello", MethodAttributes.Public
               | MethodAttributes.Static, typeof(void), new Type[] { });
            ILGenerator ilGenerator = testMethod.GetILGenerator();
            ilGenerator.EmitWriteLine("hello");
            ilGenerator.Emit(OpCodes.Ret);
            Type nestedType = nestedBuilder.CreateType();
        }

        public static void Generate()
        {
            InitAssembly();
            typeBuilder = moduleBuilder.DefineType(namespaceName + "." + typeName, TypeAttributes.Public);

            Emit_NestedMethod();
            GenerateMain();
            SaveAssembly();
            Console.WriteLine("生成成功");
        }

        static void GenerateMain()
        {
           var  mainMethod = typeBuilder.DefineMethod("Test", MethodAttributes.Public
                | MethodAttributes.Static, typeof(void), new Type[] { });
            var ilGenerator = mainMethod.GetILGenerator();

            ilGenerator.EmitWriteLine("Test");
            ilGenerator.Emit(OpCodes.Ret);
        }

        static void InitAssembly()
        {
            AssemblyName assemblyName = new AssemblyName(namespaceName);
            assemblyBuilder = AppDomain.CurrentDomain.DefineDynamicAssembly(assemblyName, AssemblyBuilderAccess.RunAndSave);
            moduleBuilder = assemblyBuilder.DefineDynamicModule(assemblyName.Name, binaryName);
        }

        static void SaveAssembly()
        {
            Type t = typeBuilder.CreateType(); //完成Type，这是必须的
            assemblyBuilder.Save(binaryName);
        }
    }
}