如何让我的DebuggerTypeProxy目标类继承自基本代理？

Question

问题: 我正在寻找一种方法来简化继承类的调试器类型代理的构造.因此,调试从另一个继承的类时,我应该看到并排侧的属性:基类的基本属性,再加上父类的新特性.

这是我到目前为止所尝试的:

1. NewA的类型代理继承自A.属性不是并排显示的; 基本属性是伞[sic]下Base.^*****
2. 包括A物业NewA,只是蒙上目前NewA到A,与[DebuggerBrowsable(RootHidden)]:Visual Studio中挂起:(

我知道我可以只将基类的属性添加到NewA代理中,但我试图避免这种情况.这对于具有许多属性的类来说太过分了.

---

说明:

我在我的DebuggerTypeProxy一些类中使用了该属性,因此我可以控制在调试期间浏览时类的外观.例如:

public class A {
    private String _someField;

    public String SomeField {
        get {return _someField;}
    }
} 

默认情况下,工具提示调试信息显示为:

...所以我使用DebuggerTypeProxy来隐藏支持字段:

[DebuggerTypeProxy(typeof(AProxy))]
public class A {
    // ...

    internal class AProxy {
        A _a;
        AProxy (A a){
            _a = a;
        }

        public String SomeField {
             get {return _a.SomeField;}
        }
    }
}

......一切都与世界是对的:

---

现在,我创建了一个继承自A的类.

public class NewA : A {
    private String _anotherField;
    public String AnotherField {
        get {return _anotherField;}
    }
}

不幸的是,在调试此类时,Visual Studio使用基类型代理(from A).这意味着我们可以看到基本SomeField属性,但我们的新AnotherField属性是隐藏的(除非你扩展Raw View,当然):

从基础中删除类型代理会A导致AnotherField显示,但不会SomeField.

---

^*尝试失败#1

/// <summary>
/// The base class
/// </summary>
[DebuggerTypeProxy(typeof(AProxy))]
public class A {
    private String _someField;

    public String SomeField {
        get { return _someField; }
    }

    protected class AProxy {
        A _a;
        protected AProxy(A a) {
            _a = a;
        }

        String SomeField {
            get { return _a.SomeField; }
        }
    }

}

/// <summary>
/// Parent class
/// </summary>
[DebuggerTypeProxy(typeof(NewAProxy))]
public class NewA : A {
    private String _anotherField;
    public String AnotherField {
        get { return _anotherField; }
    }

    // Inherit base type proxy, in an effort to display base properties
    // side-by-side with AnotherField: Doesn't work.
    protected class NewAProxy : A.AProxy {
        NewA _newA;
        protected NewAProxy(NewA newA)
            : base(newA) {
            _newA = newA;
        }

        public String AnotherField {
            get { return _newA.AnotherField; }
        }
    }
}

结果:

仍然无法正常工作.基本属性不与新属性并排放置.

Answer 1

经过几个小时的搜索和修补,我从Jare​​d Par的博客中找到了解决方案 - 一个很漂亮的解决方案.他创建了一个类型代理,它使用反射将所有成员压缩成一个列表.一些额外的DebuggerDisplay魔法使它甚至没有注意到.

// http://blogs.msdn.com/b/jaredpar/archive/2010/02/19/flattening-class-hierarchies-when-debugging-c.aspx
// by Jared Par
internal sealed class FlattenHierarchyProxy {

    [DebuggerDisplay("{Value}", Name = "{Name,nq}", Type = "{Type.ToString(),nq}")]
    internal struct Member {
        internal string Name;
        internal object Value;
        internal Type Type;
        internal Member(string name, object value, Type type) {
            Name = name;
            Value = value;
            Type = type;
        }
    }

    [DebuggerBrowsable(DebuggerBrowsableState.Never)]
    private readonly object _target;
    [DebuggerBrowsable(DebuggerBrowsableState.Never)]
    private Member[] _memberList;

    [DebuggerBrowsable(DebuggerBrowsableState.RootHidden)]
    internal Member[] Items {
        get {
            if (_memberList == null) {
                _memberList = BuildMemberList().ToArray();
            }
            return _memberList;
        }
    }

    public FlattenHierarchyProxy(object target) {
        _target = target;
    }

    private List<Member> BuildMemberList() {
        var list = new List<Member>();
        if ( _target == null ) {
            return list;
        }

        var flags = BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance;
        var type = _target.GetType();
        foreach (var field in type.GetFields(flags)) {
            var value = field.GetValue(_target);
            list.Add(new Member(field.Name, value, field.FieldType));
        }

        foreach (var prop in type.GetProperties(flags)) {
            object value = null;
            try {
                value = prop.GetValue(_target, null);
            }
            catch (Exception ex) {
                value = ex;
            }
            list.Add(new Member(prop.Name, value, prop.PropertyType));
        }

        return list;
    }
}

修改

我对课程进行了三次小修改,使其对我更有用.

首先,我希望成员按名称排序.为此,请将最后一行更改为:

return list.OrderBy(m => m.Name).ToList();

其次,在Memberstruct中,我添加了一些属性,以便在展开引用类时只显示该值:

[DebuggerBrowsable(DebuggerBrowsableState.Never)]
internal string Name;
[DebuggerBrowsable(DebuggerBrowsableState.RootHidden)]
internal object Value;
[DebuggerBrowsable(DebuggerBrowsableState.Never)]
internal Type Type;

第三,默认标志BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance意味着即使标记的成员[DebuggerBrowsable(DebuggerBrowsableState.Never)]仍将显示.为防止这种情况发生,请在此行之后:

foreach (var field in type.GetFields(flags)) {

添加这个:

// Respect DebuggerBrowsableAttributes
var debuggerBrowsableAtts = field.GetCustomAttributes(typeof(DebuggerBrowsableAttribute), true);
if (debuggerBrowsableAtts.Count() == 1) {
    var att = debuggerBrowsableAtts[0] as DebuggerBrowsableAttribute;
    if (att.State == DebuggerBrowsableState.Never) {
        continue;
    }
}

现在这个DebuggerBrowsable(DebuggerBrowsableState.Never)领域将得到尊重.您还可以将该代码添加到处理属性的foreach循环中,以使其也适用于属性.