怎样设置C ++函数，以便它可以被P使用/调用？ [英] How to set up a C++ function so that it can be used by p/invoke?

问题描述

希望这是一个brainlessly简单的问题，但它表明我缺乏与C ++的专业知识。我是一个C＃程序员，我已经做了的P / Invoke大量的工作在过去与其他人的C ++ / C的DLL。不过，这一次我决定写一个包装C ++ DLL（非托管）我自己，我然后调用从C＃我的包装的DLL。

Hopefully this is a brainlessly easy question, but it shows my lack of expertise with C++. I'm a C# programmer, and I've done extensive work with P/Invoke in the past with other people's C++/C dlls. However, this time I've decided to write a wrapper C++ dll (unmanaged) myself, and am then calling my wrapper dll from C#.

我立即运行问题到的是，我无法定义可以被p找到一个C ++函数/调用。我不知道这个语法是什么，但这里是我试图至今：

The problem I am immediately running into is that I am unable to define a C++ function that can be found by p/invoke. I don't know what the syntax for this is, but here's what I'm trying so far:

extern bool __cdecl TestFunc()
{
  return true;
}

本来我只是有这个，但它没有工作，要么

Originally I simply had this, but it did not work either:

bool TestFunc()
{
  return true;
}

，然后在C＃的一面，我有：

And then on the C# side, I have:

    public const string InterfaceLibrary = @"Plugins\TestDLL.dll";

    [DllImport( InterfaceLibrary, CallingConvention = CallingConvention.Cdecl,
        EntryPoint = "TestFunc" ), SuppressUnmanagedCodeSecurity]
    internal static extern bool TestFunc();

一切编译，但是当我执行此C＃P / Invoke调用，我得到一个System.EntryPointNotFoundException：无法找到DLL'Plugins\TestDLL.dll名为'TestFunc的切入点。

Everything compiles, but when I execute this C# p/invoke call, I get a System.EntryPointNotFoundException: Unable to find an entry point named 'TestFunc' in DLL 'Plugins\TestDLL.dll'.

当然，这必须是一些非常简单的C ++结束，我只是不知道的语法。

Surely this must be something incredibly simple on the C++ end that I just don't know the syntax for.

推荐答案

您需要使用的externC以及 __ declspec（出口），就像这样：

You'll want to use extern "C" as well as __declspec(export), like so:

extern "C" _declspec(dllexport)  bool TestFunc()
{
    return true;
}

有关详情，请参阅MSDN的编组类型的。

这篇关于怎样设置C ++函数，以便它可以被P使用/调用？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！