Dllimport，外部功能 [英] Dllimport, extern functionality

问题描述

您好。在C＃中，你有Dllimport和extern一起从特定的DLL导入一个特定的函数。我想知道如果可能的话，如何用C ++实现它们的功能。提前致谢。



例如在C＃：

[的DllImport（ setupapi.dll，字符集=字符集:: Seeifdef，入口点= SetupDiGetClassDevs）]

的extern C HDEVINFO SetupDiGetClassDevsUM（

LPGUID ClassGuid，

PCTSTR枚举器，

HWND hwndParent，

DWORD标志）;



到C ++：？

解决方案

它是在C ++有点不同。

'pre>外部的 C
{
__declspec（dllimport的）HDEVINFO SetupDiGetClassDevsUM（LPGUID ClassGuid，PCTSTR枚举，HWND hwndParent，DWORD标志）;
}

但没有那么不同。

我不知道C＃但是在C ++中你还需要链接到导出此函数的DLL，方法是将其导入库添加到Visual Studio中的链接器输入列表或类似 #pragma comment（lib，SetupAPI.lib）

大多数Windows库已经提供了标准的C接口，这些接口在相关的头文件中定义。只需查看 MSDN文档 [ ^ ]您感兴趣的API调用，它将为您提供调用的详细信息，参数， .h 和 .lib 需要使用它的文件。

Hi. In C# you have Dllimport and extern going together to import a specific function from a specific DLL. I want to know how to implement their functionalities in C++ if it''s possible. Thanks in advance.

E.g. in C#:
[DllImport("setupapi.dll" , CharSet = CharSet::Seeifdef, EntryPoint="SetupDiGetClassDevs")]
extern "C" HDEVINFO SetupDiGetClassDevsUM(
LPGUID ClassGuid,
PCTSTR Enumerator,
HWND hwndParent,
DWORD Flags);

To C++:?

解决方案

It is a little different in C++.

extern "C"
{
__declspec( dllimport ) HDEVINFO SetupDiGetClassDevsUM( LPGUID ClassGuid, PCTSTR Enumerator, HWND hwndParent, DWORD Flags );
}

but not that different.
I don''t know about C# but in C++ you''ll also need to link to the DLL that exports this function, by adding its import library to the linker input list in Visual Studio or some thing like #pragma comment(lib,"SetupAPI.lib")

Most Windows libraries already provide standard C interfaces which are defined in their associated header files. Just check the MSDN documentation[^] for the API call you are interested in, and it will give you the details of the call, parameters, .h and .lib files needed to make use of it.

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