显式方法的覆盖覆盖隐藏属性

Question

有一个有一个属性的类:

public class BaseClass
{
  public virtual string Property1 { get; set; }
}

现在我使用一些方法覆盖创建派生类型:

[Test]
public void name ()
{
  var assemblyBuilder = AppDomain.CurrentDomain.DefineDynamicAssembly (new AssemblyName ("Test"), AssemblyBuilderAccess.RunAndSave);
  var moduleBuilder = assemblyBuilder.DefineDynamicModule ("Test.dll");
  var derivedBuilder = moduleBuilder.DefineType ("DerivedClass", TypeAttributes.Public, typeof (BaseClass));

  const MethodAttributes methodAttributes = MethodAttributes.Private | MethodAttributes.Virtual | MethodAttributes.SpecialName | MethodAttributes.NewSlot;

  var getterOverride = derivedBuilder.DefineMethod (
      "get_Property1",
      methodAttributes,
      typeof (string),
      Type.EmptyTypes);
  var getterILGenerator = getterOverride.GetILGenerator();
  getterILGenerator.Emit (OpCodes.Ldnull);
  getterILGenerator.Emit (OpCodes.Ret);
  derivedBuilder.DefineMethodOverride (getterOverride, typeof (BaseClass).GetMethod ("get_Property1"));

  var setterOverride = derivedBuilder.DefineMethod (
      "set_Property1",
      methodAttributes,
      typeof (void),
      new[] { typeof (string) });
  var setterILGenerator = setterOverride.GetILGenerator ();
  setterILGenerator.Emit (OpCodes.Ret);
  derivedBuilder.DefineMethodOverride (setterOverride, typeof (BaseClass).GetMethod ("set_Property1"));

  var derivedType = derivedBuilder.CreateType();
  var props = derivedType.GetProperties (BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance);

  assemblyBuilder.Save ("Test.dll");

  Assert.That (props, Has.Length.EqualTo (1));
}

生成的类型不再包含该属性.奇怪的是,如果更改至少一个方法定义的methodAttributesto MethodAttributes.Public,则属性会再次出现.

好像是个bug？

编辑: peverify不会出错.

编辑:( Fabian Schmied的重要评论)

ECMA-335分区II,10.3.3:"如果类型通过MethodImpl覆盖继承的方法,它可以扩大或缩小该方法的可访问性."

Answer 1

由于规范（ECMA-335，II.10.3.3）明确允许缩小通过 MethodImpl 覆盖的方法的可见性（“显式覆盖”，由 Reflection.Emit 通过 TypeBuilder.DefineMethodOverride 表示），我相信这确实是一个Reflection 实现中的错误，应通过Microsoft Connect报告。