什么是是非非托管类型和托管类型之间的区别？ [英] What's the difference between a non-unmanaged type and a managed type?

问题描述

当我写了下面的代码片段为实验目的，提出了悬停误差（见截图）：

When I wrote the following snippet for experimenting purposes, it raised the hover-error (see screenshot):

无法声明指针非非托管式动态

Cannot declare pointer to non-unmanaged type 'dynamic'

该片段：

dynamic* pointerToDynamic = &fields;

虽然明确不允许的代码（你不能把一个托管类型的地址），它提出我的问题是：什么是的非非托管类型？它不同于托管类型？或只是Visual Studio的努力很有趣？

While the code is clearly not allowed (you cannot take the address of a managed type), it raised with me the question: what is a non-unmanaged type and how is it different to a managed type? Or is it just Visual Studio trying to be funny?

推荐答案

<击>有非托管和非托管的指针之间的差异。

一个管理的指针的是一个句柄，在托管堆中的对象，据我所知是在托管C ++才可用。它等价的C＃的参考的一个对象。非托管指针，而另一方面，就相当于一个传统的C风格的指针，即一个存储单元的地址; C＃提供了一元&安培; 操作符，固定关键字和不安全上下文的。

A managed pointer is a handle to an object on the managed heap, and AFAIK is available in managed C++ only. It is equivalent of C# reference to an object. Unmanaged pointer, on the other hand, is equivalent of a traditional C-style pointer, i.e. address of a memory location; C# provides unary & operator, fixed keyword and unsafe context for that.

您正试图获得一个指向一个管理域（动态实际上 System.Object的是伪装），而C＃允许指针的非托管的对象而已，因此措辞：你的类型为非非托管

You are trying to get a pointer to a managed field (dynamic is actually System.Object is disguise), while C# allows pointers to unmanaged objects only, hence the wording: your type is non-unmanaged.

更多关于这里此一点。

A bit more on this here.

更新：，以使其更清晰，托管C ++支持经典的C风格的指针的和的引用。但是为了保持C ++术语一致，他们被称为的非托管的和的管理的指针后，相应地。 C＃也支持指针（明确地不安全上下文）和引用（隐时引用类型的对象是参与），但后者的不可以被称为管理指针，他们只是引用

Update: to make it more clear, managed C++ supports classic C-style pointers and references. But to keep C++ terminology consistent, they are called unmanaged and managed pointers, correspondingly. C# also supports pointers (explicitly in unsafe context) and references (implicitly whenever objects of reference types are involved), but the latter is not called "managed pointers", they are just references.

要总结一下：。在C ++中有非托管和托管指针，在C＃中 - 非托管指针和引用

To sum up: in C++ there are unmanaged and managed pointers, in C# - unmanaged pointers and references.

希望这是有道理的吧。

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