C ++中的DLL导出和继承 [英] DLL export and inheritance in C++

问题描述

我正在尝试从DLL中导出一个类及其基类，如下所示:

I'm trying to export a class and its base class from a DLL like this:

#ifdef MY_EXPORTS
    #define DECLSPEC_TEST __declspec(dllexport)
#else
    #define DECLSPEC_TEST __declspec(dllimport)
#endif


class DECLSPEC_TEST BaseClass
{
  // stuff.
};

class DECLSPEC_TEST DerivedClass : public BaseClass
{
  // This class only has a constructor which initializes the class differently.

};

但是我尝试在另一个DLL中使用此类，但我不断收到错误消息:

But I try to use this class in another DLL, I keep getting an error:

error LNK2019: unresolved external symbol 
"__declspec(dllimport) public: __thiscall DerivedClass::DerivedClass(void)"
 (__imp_??0DerivedClass@@QAE@XZ) referenced in function 
"public: __thiscall SomeOtherClass::SomeOtherClass(void)" (??0SomeOtherClass@@QAE@XZ)  

我还用PE Explorer查看了导出的DLL，但在导出列表中看不到派生类.

I also looked at my exporting DLL with PE Explorer and I can't see the derived class in the exports list.

当我尝试在其他DLL中使用基类时，效果很好.

When I try to use the base class in my other DLL it works fine.

我做错了什么?

推荐答案

好，我不知道如何解释这个问题，但是我将派生类的构造函数的实现放在CPP文件中，而不是在类定义中，错误消失了...
谢谢大家:)

Ok, I don't know how to explain this but I put the implementation of the derived class' constructor in a CPP file instead of within the class definition and the error went away...
thanks everybody :)

这篇关于C ++中的DLL导出和继承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！