Question

我有以下代码：

public class Ancestor
{
    public string Property {get; protected set;}
}

public class Base : Ancestor
{
    public string Property {get; set;}
}

public class Derived : Base
{
    public Derived(string message)
    {
        //I need both properties to have the message value
    }
}

Ancestor和Base类不是我的代码，我无法改变它们有没有办法将Ancestor的属性设置为消息的值？
显然，简单地执行以下操作将无法正常工作

Ancestor ancestor = this;
ancestor.Property = message

因为setter受到保护。

Answer 1

仅通过反思：

 public class Derived : Base
{
    public Derived(string message)
    {
        Type type = typeof(Ancestor);
        Ancestor a = (Ancestor)this;
        type.GetProperty("Property").SetMethod.Invoke(a, new[] { message });
    }
}

Answer 2

我找到了满足我需求的解决方案。我的Ancestor类来自一个接口：

public interface IAncestor
{
    string Property { get; }
}

我所做的是使用显式接口声明，如下所示：

public class Derived : Base, IAncestor
{
    public Derived(string message)
    {
        Property = message;
        base.Property = message;
    }
    string IAncestor.Property{get { return Property; }}
}

现在接下来的测试通过了：

[TestMethod]
public void ValidatePropertyIsFullyPopulated()
{
    const string expectedMessage = "hello!";
    var derived = new Derived(expectedMessage);
    Base baseClass = derived;
    IAncestor ancestor = derived;
    Assert.AreEqual(expectedMessage, derived.Property);
    Assert.AreEqual(expectedMessage, baseClass.Property);
    Assert.AreEqual(expectedMessage, ancestor.Property);

    //Notice that this Assert WILL fail because Ancestor.Property is
    //not marked as virtual.
    Ancestor ancestorClass = derived;
    //Assert.AreEqual(expectedMessage, ancestorClass.Property);
}

设置隐藏基类的属性

2 个答案: