如何动态实现代理模式？(How do I dynamically implement the Proxy Pattern?)

 我正在重新审视我去年写的班级跟踪（脏逻辑）。 目前我有一个处理所有状态跟踪的超级基类，但是我需要跟踪的每个属性需要遵循标准get { return _x; } set { _isDirty = true; _x = value; } get { return _x; } set { _isDirty = true; _x = value; } 工作方式。 
 
 在使用Entity Framework并阅读代理模式之后 ，我希望有更好的方法来实现我的IsDIrty Logic，同时能够利用自动实现的属性？ 
 
 说实话，我不知道我在说什么。 有没有办法可以做如下的事情： 
 
public class Customer : ITrackable
{
    [TrackState(true)] // My own attribute
    public virtual string Name { get;set;}

    [TrackState(true)]
    public virtual  int Age { get;set;}

    // From ITrackable
    public bool IsDirty { get; protected set; }

}
 
 然后实现一个动态代理，它将使用反射（或另一个神奇的解决方案）在使用TrackState属性在属性上设置值之前先调用另一个方法。 
 
 显然，我可以通过创建一个phyiscal代理类并使用IoC来轻松完成这项工作： 
 
public class CustomerProxy : Customer
{
    Customer _customer;

    public override string Name 
    {
        get { return _customer.Name; }
        set { IsDirty = true; return _customer.Name; }
    }

    // Other properties
}
 
 但我不想为每个对象做这个，否则我现有的解决方案没有任何好处。 希望有人能满足我的好奇心，或者至少告诉我EF如何实现它。 

I'm revisiting my class tracking (dirty logic), which I wrote last year. Currently I have an uber base class that deals with all the state tracking, but each property whos values I need to track needs to stick to the standard get { return _x; } set { _isDirty = true; _x = value; } way of working.
 
After playing with Entity Framework and reading up on the Proxy Pattern, I was hoping there was a nicer way to implement my IsDIrty Logic whilst being able to make use of auto implemented properties?
 
To be completely honest, I haven't a clue of what I'm talking about. Is there a way I can do something like the following:
 
public class Customer : ITrackable
{
    [TrackState(true)] // My own attribute
    public virtual string Name { get;set;}

    [TrackState(true)]
    public virtual  int Age { get;set;}

    // From ITrackable
    public bool IsDirty { get; protected set; }

}
 
And then implement a dynamic proxy which will use reflection (or another magical solution) to call another method first before setting the values on the properties with the TrackState attribute.
 
Obviously I could easily do this by creating a phyiscal proxy class and use IoC:
 
public class CustomerProxy : Customer
{
    Customer _customer;

    public override string Name 
    {
        get { return _customer.Name; }
        set { IsDirty = true; return _customer.Name; }
    }

    // Other properties
}
 
But I don't fancy having to do this for every object, otherwise there's no benefit from my existing solution. Hope someone can satisfy my curiosity, or at least tell me how EF achieves it.

原文：https://stackoverflow.com/questions/3702512