C++ 未解析的外部符号？

Question

在 VS 中处理我的项目时，我决定将源代码拆分成单独的文件。然而，在尝试编译之后，我得到了这个错误：

LNK2019 unresolved external symbol "public: __thiscall CS_RawUser::CS_RawUser(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >,class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >,int)" (??0CS_RawUser@@QAE@V?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@0H@Z) referenced in function "void __cdecl mkUser(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >,class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >,class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >)" (?mkUser@@YAXV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@00@Z)

我在 google 上搜索并发现了多个类似的问题。但是，对于缺少的实现，他们所有人都有相同的答案。然而，在我的源代码中（除非我大错特错）错误中提到的函数已正确定义。

CS_OBJ.cpp:

class CS_RawUser
{
private:
    string m_username;
    string m_password;
    int m_level;

string compileDatabaseEntry()
{
    return "CSEC_INSTANCE_USER:" + m_username + "," + m_password + "," + to_string(m_level);
}

public:
    CS_RawUser(string username, string password, int level)
    {
        m_username = username;
        m_password = password;
        m_level = level;
    }
    string username() { return m_username; }
    string password() { return m_password; }
    int level() { return m_level; }
    string compile() { return compileDatabaseEntry(); }
};

CS_OBJ.h:

class CS_RawUser
{
private:
    std::string m_username;
    std::string m_password;
    int m_level;
    std::string compileDatabaseEntry();
public:
    CS_RawUser(std::string username, std::string password, int level);
    std::string username();
    std::string password();
    int level();
    std::string compile();
};

Answer 1

您的实施文件不应重新定义 class。这是可能的（正确的）代码：

CS_OBJ.h:

class CS_RawUser
{
public:
    CS_RawUser(std::string username, std::string password, int level);
};

CS_OBJ.cpp

#include "CS_OBJ.h"

CS_RawUser::CS_RawUser(std::string username, std::string password, int level)
{
    ... // initialization here...
}

C++ 未解析的外部符号？

c++ unresolved external symbol?

c++

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