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如何使用反射访问私有基类字段

[英]How to access a private base class field using Reflection

I'm trying to set the private "visible" field on a variable of type BaseClass. 我正在尝试在BaseClass类型的变量上设置私有的“可见”字段。

  • ChildClass ChildClass
    • BaseClass BaseClass的
      • "visible" field “可见”字段

I've successfully accessed the variable of type ChildClass, and the FieldInfo for the "visible" field on the BaseClass. 我已经成功访问​​了ChildClass类型的变量,以及BaseClass上“ visible”字段的FieldInfo。

But when I try to set/get the value of the field, I get the error System.Runtime.Remoting.RemotingException: Remoting cannot find field 'visible' on type 'BaseClass'. 但是,当我尝试设置/获取字段的值时,出现错误System.Runtime.Remoting.RemotingException:远程处理无法在类型'BaseClass'上找到字段'visible'。

So Is there a way to "down cast" a variable of type ChildClass to BaseClass in order for the reflection to work? 那么,是否有一种方法可以将“ ChildClass”类型的变量“强制转换”为BaseClass,以便进行反射?


Edit: The exact code I'm using: 编辑:我正在使用的确切代码:

// get the varible
PropertyInfo pi = overwin.GetProperty("Subject", BindingFlags.Instance|BindingFlags.Public);
CalcScene scene = (CalcScene) pi.GetValue(inwin, null);

// <<< scene IS ACTUALLY A TYPE OF DisplayScene, WHICH INHERITS FROM CalcScene

// get the 'visible' field
Type calScene = typeof(CalcScene);
FieldInfo calVisible = calScene.GetField("visible",BindingFlags.Instance|BindingFlags.NonPublic);

// set the value
calVisible.SetValue(scene, true); // <<< CANNOT FIND FIELD AT THIS POINT

The exact class structure: 确切的类结构:

class CalcScene  
{
    private bool visible;
}

class DisplayScene : CalcScene  
{
}

you can try like this 你可以这样尝试

    class B
    {
        public int MyProperty { get; set; }
    }

    class C : B
    {
        public string MyProperty2 { get; set; }
    }

    static void Main(string[] args)
    {
        PropertyInfo[] info = new C().GetType().GetProperties();
        foreach (PropertyInfo pi in info)
        {
            Console.WriteLine(pi.Name);
        }
    }

produces 产生

MyProperty2
    MyProperty

Here is some code that demonstrates the difference between getting a field vs a property: 以下是一些代码,演示了获取字段与属性之间的区别:

  public static MemberInfo GetPropertyOrField(this Type type, string propertyOrField)
  {
      MemberInfo member = type.GetProperty(propertyOrField, BindingFlags.Public | BindingFlags.Instance | BindingFlags.IgnoreCase);
      if (member == null)
          member = type.GetField(propertyOrField, BindingFlags.Public | BindingFlags.Instance | BindingFlags.IgnoreCase);

      Debug.Assert(member != null);
      return member;
  }

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