当属性类型未知时，通过反射创建属性acctor的委托 [英] Create delegate for property acessor obtained via reflection when property type unknown

问题描述

在.NET 2.0（使用C＃3.0）中，当我在编译时不知道其类型时，如何为通过反射获取的属性访问器创建代理？

In .NET 2.0 (with C# 3.0), how can I create a delegate for a property accessor obtained via reflection when I don't know its type at compile time?

例如如果我有类型为 int 的财产，我可以这样做：

E.g. if I have property of type int, I can do this:

Func<int> getter = (Func<int>)Delegate.CreateDelegate(
    typeof(Func<int>),
    this, property.GetGetMethod(true));
Action<int> setter = (Action<int>)Delegate.CreateDelegate(
    typeof(Action<int>),
    this, property.GetSetMethod(true));

但是如果我不知道在编译时的属性是什么类型，我不知道

but if I do not know what type the property is at compile time, I don't know how to do it.

推荐答案

您需要的是：

Delegate getter = Delegate.CreateDelegate(
    typeof(Func<>).MakeGenericType(property.PropertyType), this,
    property.GetGetMethod(true));
Delegate setter = Delegate.CreateDelegate(
    typeof(Action<>).MakeGenericType(property.PropertyType), this,
    property.GetSetMethod(true));

然而，如果你这样做是为了表演，你还会简单的说，因为你将需要使用 DynamicInvoke（），这是 slooow 。您可能想要查看元编程来编写一个包含/取回对象的包装器。或者看看HyperDescriptor，为你做这个。

however, if you are doing this for performance, you are still going to come up short, since you would need to use DynamicInvoke(), which is slooow. You might want to look at meta-programming to write a wrapper that takes/returns object. Or look at HyperDescriptor which does this for you.

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