使用dllimport进行扩展 [英] Use dllimport for class extended

问题描述

我有那段代码：



C ++：

I have that code:

C++:

class testfunction {
  public:
	virtual double operator()(double) = 0;
};

我希望在C＃中使用此课程，例如



C＃

and i want use this class in C#, example

C#

class myCSharpClass: testfunction
{
}

我怎么做？



我是什么尝试过：

How i can do it?

What I have tried:

extern "C"
{
  class testfunction {
  public:
	virtual double operator()(double) = 0;
  };
}

推荐答案

之前已经提出并回答过：

如何在c＃中使用c ++类和函数？ [ ^ ]

如何在C＃应用程序中使用DllExport C ++类 - Stack Overflow [ ^ ]



一些有用的链接：

如何制作C ++类 [ ^ ]

在.NET应用程序中使用非托管C ++库（DLL） [ ^ ]

HowTo：从DLL导出C ++类 [ ^ ]

托管/非托管代码互操作性概述 [ ^ ]

This has been asked and answered before:
How to use c++ classes and functions in c#?[^]
How do I DllExport a C++ Class for use in a C# Application - Stack Overflow[^]

Some useful links:
How to Marshal a C++ Class[^]
Using Unmanaged C++ Libraries (DLLs) in .NET Applications[^]
HowTo: Export C++ classes from a DLL[^]
An Overview of Managed/Unmanaged Code Interoperability[^]

一个解决方案是使用Bridge模式。

软件设计模式 - 维基百科，免费的百科全书 [ ^ ]

桥模式 - 维基百科，免费的百科全书 [ ^ ]



因此，您创建了一个桥，允许您模拟从非托管C ++类派生的托管C＃类。当然，你不能直接这样做。但是，在C ++ / CLI中创建一个模拟原始界面的托管界面并不难，然后还有一个派生自原始界面的类并将所有调用转发到托管界面。



因为它需要几行代码，所以我不会写它。如果你知道如何在本机类中保存托管数据，那么实现它应该相对简单。



另一方面，你真的需要实现一个使用托管C＃类的原生C ++抽象类？实际上，混合托管代码和本机代码确实需要一些关于互操作的知识。



顺便说一下，如果你真的想写这样的代码，这样的书可能非常有用： Manning | C ++ / CLI在行动中 [ ^ ]



PS另请参阅我的问题和第二个解决方案。

One solution would be to use Bridge pattern.
Software design pattern - Wikipedia, the free encyclopedia[^]
Bridge pattern - Wikipedia, the free encyclopedia[^]

Thus you create a bridge that would allow you to simulate a managed C# class deriving from an unmanaged C++ class. Of course, you cannot directly do that. But it is not hard to create a managed interface in C++/CLI that mimic your original interface and then have also a class that derive from your original interface and forward all calls to the managed interface.

As it required a few lines of code, I won't write it. If you know how to hold managed data inside a native class, then it should be relatively trivial to implement.

On the other hand, do you really need to implement a native C++ abstract class using managed C# class? In fact, mixing managed and native code does required some knowledge about interop.

By the way a book like this one might be very useful if you really want to write such code: Manning | C++/CLI in Action[^]

P.S. See also my comments under question and second solution.

看一下这个例子：如何使用C＃在C ++中创建dll - Stack Overflow [ ^ ]



C ++代码（DLL），例如。 math.cpp，编译为HighSpeedMath.dll：

Take a look at this example: How to create dll in C++ for using in C# - Stack Overflow[^]

C++ Code (DLL), eg. math.cpp, compiled to HighSpeedMath.dll:

extern "C"
{
    __declspec(dllexport) int __stdcall math_add(int a, int b)
    {
        return a + b;
    }
}

C＃代码，例如。 Program.cs：

C# Code, eg. Program.cs:

namespace HighSpeedMathTest
{
    using System.Runtime.InteropServices;

    class Program
    {
        [DllImport("HighSpeedMath.dll", EntryPoint="math_add", CallingConvention=CallingConvention.StdCall)]
        static extern int Add(int a, int b);

        static void Main(string[] args)
        {
            int result = Add(27, 28);
        }
    }
}

这篇关于使用dllimport进行扩展的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！