C＃中事件的反射和私有委托字段 [英] Reflection and private delegate fields of events in c#

问题描述

我可能正在做一些愚蠢的事情，但是事情就这样了。

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

我正在尝试通过反思从公共事件中获取FieldInfo。

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

检查此功能：

  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;
  }

调用PlotAllFields（typeof（Foo））;返回值：

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

• 测试


• 事件


• RoutedEvent

调用PlotAllFields（typeof（Bar））;返回：

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

• 测试

我了解事件背后的代表是私有字段
，因此我无法在子类上访问它们。

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

然后我尝试了：PlotAllFields（typeof（FrameworkElement））; //来自WPF

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

• _themeStyleCache


• _styleCache


• _templatedParent


• _templateChild


• _flags


• _flags2


• _parent


• _inheritableProperties


• MeasureRequest


• ArrangeRequest


• sizeChangedInfo
>

• _parentIndex


• _parent


• _proxy


• _contextStorage

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

嗯... FrameworkElement类的14个事件在哪里？

推荐答案

FrameworkElement不使用类似字段的事件，它会调用 AddHandler 和 RemoveHandler 。大多数情况下，他们没有附加处理程序，因此WPF使用的系统更加节省空间。例如，这是来自Reflector的Loaded事件：

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);
    }
}

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