实例化一个使用泛型类反射 [英] instantiate a generic class using reflection

问题描述

^{[注意：我不相信这个问题是一个上面链接的副本，我在下面的更新说明]}

^{[NOTE: I don't believe this question is a duplicate of the one linked above, as I explain in the UPDATE below.]}

有什么办法来定义/使用反射实例化一个泛型类？

Is there any way to define/instantiate a generic class using reflection?

所以我有一堆类，其中每个拥有共享其主人的类型泛型类的一个实例：

So I have a bunch of classes, each of which owns an instance of a generic class that shares the type of its owner:

public class GenericClass<T>
{
    T Owner { get; set; }
    public GenericClass(T owner) { Owner = owner; }
}
public class MyClass
{
    private GenericClass<MyClass> myGenericObject;
    public MyClass() { myGenericObject = new GenericClass<MyClass>(this); }
}

这工作，但当然我必须明确地指定MyClass的为在GenericClass定义的说法。我希望能够做这样的事：

This works, but of course I have to explicitly specify "MyClass" as the argument in the GenericClass definition. I'd like to be able to do something like this:

private GenericClass<typeof(this)> myGenericObject; // Error: invalid token

反正是有在编译时动态指定的通用对象的类型的基础上，包含类

Is there anyway to dynamically specify the type of the generic object at compile time, based on the containing class?

更新：来自的这些的问题，我才知道，我可以实例化一个局部变量，像这样：

UPDATE: After reading the answers from these questions, I learned that I could instantiate a local variable like so:

var myGenericObject = Activator.CreateInstance(typeof(GenericClass<>).MakeGenericType(this.GetType()));

但是，当然，在这个关键字只有一个方法中可用的（因此，例如，我可以把下面这行代码的 MyClass的的构造函数）。但我不能使用这种方法来定义的实例的变量（即 myGenericObject ，在上面的代码）。有什么办法来动态指定一个泛型实例变量？

but, of course, the this keyword is only available inside a method (so, for example, I could put this line of code in the constructor of MyClass). But I cannot use this approach to define an instance variable (i.e., myGenericObject, in the code above). Is there any way to specify a generic instance variable dynamically?

推荐答案

关于你的更新，你可以通过任何键入到 MakeGenericType 。例如，下面的也可以工作：

Regarding your update, you can pass any Type to MakeGenericType. For example, the following also works:

var myObject = new MyClass();

var myGenericObject = Activator.CreateInstance(typeof(GenericClass<>).MakeGenericType(typeof(MyClass)), myObject);

Console.WriteLine(myGenericObject.GetType());

输出：

Outputs:

ConsoleApplication1.GenericClass`1[ConsoleApplication1.MyClass]

myObject.GetType（）也做同样的事情：

var myGenericObject = Activator.CreateInstance(typeof(GenericClass<>).MakeGenericType(myObject.GetType()), myObject);

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