Reflection and private delegate fields of events in c#

问题

I'm probably doing something silly, but here it goes.

I'm trying to get the FieldInfo from a public event via reflection.

Check this function:

  public void PlotAllFields(Type type) {
      BindingFlags all = BindingFlags.Instance | BindingFlags.NonPublic | BindingFlags.Public;
      FieldInfo[] fields = type.GetFields(all);
      Console.WriteLine(type + "-------------------------");
      foreach (var fieldInfo in fields) {
          Console.WriteLine(fieldInfo.Name);
      }
  }

  public class Bar : Foo {}

  public class Foo {
      public string Test;
      public event EventHandler Event;
      public event RoutedEventHandler RoutedEvent;
  }

The call PlotAllFields(typeof(Foo)); returns:

Test
Event
RoutedEvent

The call PlotAllFields(typeof(Bar)); returns:

Test

I understand that the delegates behind the events are private fields so I can't access them on the subclass. So far so good.

Then I tried: PlotAllFields(typeof(FrameworkElement)); //from WPF

_themeStyleCache
_styleCache
_templatedParent
_templateChild
_flags
_flags2
_parent
_inheritableProperties
MeasureRequest
ArrangeRequest
sizeChangedInfo
_parentIndex
_parent
_proxy
_contextStorage

Well... Where are the 14 events of FrameworkElement class???

回答1:

FrameworkElement doesn't use field-like events, it makes calls to AddHandler and RemoveHandler. Most of the time they don't have handlers attached, so WPF uses a system that is more space-efficient. For example, here is the Loaded event, from Reflector:

public event RoutedEventHandler Loaded
{
    add
    {
        base.AddHandler(LoadedEvent, value, false);
    }
    remove
    {
        base.RemoveHandler(LoadedEvent, value);
    }
}

回答2:

try these binding flags

BindingFlags.Default |
BindingFlags.FlattenHierarchy |
BindingFlags.Instance |
BindingFlags.NonPublic |
BindingFlags.Public

http://msdn.microsoft.com/query/dev10.query?appId=Dev10IDEF1&l=EN-US&k=k(SYSTEM.REFLECTION.BINDINGFLAGS);k(TargetFrameworkMoniker-%22.NETFRAMEWORK,VERSION%3dV3.5%22);k(DevLang-CSHARP)&rd=true

来源：https://stackoverflow.com/questions/3618085/reflection-and-private-delegate-fields-of-events-in-c-sharp

标签

wpf

events

reflection

delegates