由网友(那抹嶶笶ゐ何侞茈淒涼)分享简介：我们正在考虑使用托管C ++编写.Net的调用包装对于一些传统的C ++库。We're looking at writing a .Net-callable wrapper for some legacy C++ libraries using managed C++.这一切看起来pretty的方便。有什么需要我们...

我们正在考虑使用托管C ++编写.Net的调用包装对于一些传统的C ++库。

We're looking at writing a .Net-callable wrapper for some legacy C++ libraries using managed C++.

这一切看起来pretty的方便。有什么需要我们注意？

It all looks pretty easy. Is there anything we need to watch out for?

推荐答案

我发现它通常很容易将保鲜膜中的C ++ / CLI一些现有的C ++库和遇到的比较少的缺陷。那些我还记得是：

I found it generally quite easy to wrap some existing C++ libraries in C++/CLI and encountered comparatively few pitfalls. The ones I can remember were:

在混合非托管C ++ $ C $在相同的可执行文件/ DLL的C和C ++ / CLI code是一个非常糟糕的主意。我碰到的问题与竞争的内存管理器在关机时间的方式（基本上是.NET运行时和普通C ++运行时，其中踩着对方的脚趾，当它来清理内存关机，导致不确定性的行为，以其中一个释放的）。取而代之的是静态的传统的C ++库链接到C ++ / CLI库，我创建了一个包含了传统的C ++和链接，对在C ++ / CLI DLL，它解决了这个问题一劳永逸。系统DLL 如果您的code是用枚举，不得不将那些在适当的C ++ / CLI枚举类，否则其他.NET语言将无法看到和使用它们。 在C ++ / CLI对象只能容纳指向非托管C ++对象。不幸的是在某些情况下，这意味着你必须创建瘦包装层来处理特定对象。我的最爱是，我不得不要么包装的boost :: shared_ptrs这种方式（从而添加另一层间接的），或者把它们放进shared_ptrs与空删除器穿越.NET /本地边界之后。无论是当你必须处理使用这种构造有很多的API是非常好的。 RAII没有越过这个边界，因此被警告，你将有一些时间来投入到调整到了.NET的方式相匹配。 在C ++ / CLI没有做多继承，因此，如果您的旧库的利用，你可能需要使用这个接口模型等。 在内部编组code似乎能够处理最POD转换，但你必须查找/借code可以转换的std ::字符串等，这code是各地，几在谷歌分钟应该把它（对不起，没有方便的在这里的时刻的任何链接）。 Mixing unmanaged C++ code and C++/CLI code in the same executable/DLL is a really bad idea. I've run into problems with competing memory managers at shutdown time that way (basically the .NET runtime and the regular C++ runtime where stepping on each other's toes when it came to cleaning up memory on shutdown, resulting in non-deterministic behaviour as to which one freed what). Instead of linking the static legacy C++ library into the C++/CLI library, I created a DLL containing the legacy C++ and linked that against the C++/CLI DLL, which solved the problem once and for all. If your code is using enums, you have to wrap those in the appropriate C++/CLI enum classes, otherwise other .NET languages won't be able to see and use them. C++/CLI objects can only hold pointers to unmanaged C++ objects. Unfortunately in certain cases, this means you will have to create thin wrapper layers to handle certain objects. My "favourite" was that I had to either wrap boost::shared_ptrs that way (and thus add another layer of indirection) or put them into shared_ptrs with null deleters after crossing the .NET/native boundary. Neither is very nice when you have to deal with APIs that use this sort of construct a lot. RAII doesn't cross this boundary, so be warned, you will have to invest some time into tweaking it to match the .NET way. C++/CLI doesn't do multiple inheritance, so if your legacy library is making use of that you might have to model this using interfaces etc. The internal marshalling code seems to be able to handle most POD conversions, but you'll have find/borrow code that converts std::strings etc. This code is around, a few minutes on Google should bring it up (sorry, don't have any links handy here at the moment).