在运行时与另一个基类更改/交换基类 [英] Change/Swap base class at runtime with another base class

问题描述

听起来像个愚蠢的主意，但我想知道是否有可能。

Sounds like silly idea but I was wondering if it's possible somehow.

是否可以在运行时更改派生类的基类？当然，有很多假设，还有为什么有人会这样做的问题以及它的不良设计等等。

Is it possible to change the base class of a derived class at runtime? Of course, there are lot of ifs and buts and the the question of why would someone do it and its a bad design probably and all that.

把所有这些都放在一边（即使它们可能是完全有效的），也可以说，只是为了踢球或显示你的书呆子，是否可以用C＃或任何语言编写

Keeping all those aside (even though they might be perfectly valid), let's say, just for kicks or to show your nerdiness, is it possible in C# or any language for that matter?

是这样的：

public class baseOriginal {
    public string justAProperty;
}

public class baseSwapped {
    public int sillyNumber;
}

public class derivedClass : baseOriginal {
   public bool iAmDumb;
}

void Main() {
    baseOriginal derived = new derivedClass ();
    Console.WriteLine(derived.justAProperty);
    baseSwapped derivedSwapped = (??);
    Console.WriteLine(derivedSwapped.sillyNumber);
}

推荐答案

我能想到的最接近的东西的内容如下：

The closest thing I can think of is the following:

http://msdn.microsoft.com/zh-cn/library/dd264736.aspx

static void Main(string[] args)
{
    ExampleClass ec = new ExampleClass();
    // The following line causes a compiler error if exampleMethod1 has only
    // one parameter.
    //ec.exampleMethod1(10, 4);

    dynamic dynamic_ec = new ExampleClass();
    // The following line is not identified as an error by the
    // compiler, but it causes a run-time exception.
    dynamic_ec.exampleMethod1(10, 4);

    // The following calls also do not cause compiler errors, whether 
    // appropriate methods exist or not.
    dynamic_ec.someMethod("some argument", 7, null);
    dynamic_ec.nonexistentMethod();
}

class ExampleClass
{
    public ExampleClass() { }
    public ExampleClass(int v) { }

    public void exampleMethod1(int i) { }

    public void exampleMethod2(string str) { }
}

我不知道动态语言运行时是否可以执行您想要的操作。

I have no idea if the dynamic language runtime can do what you want it to do.

通过将至少一个
定义为一个接口，然后将从一个类型派生到另一个的
转换，可以得到从这两种类型派生的
。

Closest you could get would be to derive from both types by defining at least one as an interface, then casting derived from one to the other.

根据这个建议可以满足他想要做的事的例子，我将不得不同意，这也是他实际想要做的一个更好的设计。

I would have to agree, based on the example this suggestion would satisfy what he wants to do, it also is a better design then what he actually wants to do.

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