c++ - C++ “unresolved external symbol”使用来自不同项目的 namespace

我有两个项目(分别称为Test和Intrados)。在Intrados内部，我具有以下 namespace :

#include "Mapper.h"
#include "Director.h"
#include "Driver.h"
#include <iostream>
#include <string>
using namespace std;

namespace IntradosMediator {
    void addVehicle(string);
}

void IntradosMediator::addVehicle(string vehicleName) {
    Mapper* mapper = Mapper::getInstance();
    mapper->addVehicle(vehicleName);
}

在Intrados项目中，调用“IntradosMediator::Mapper(addVehicle)”就可以了。但是，在项目Test中，以下代码会产生链接错误:

#include "IntradosMediator.cpp"
#include "Mapper.h"
using namespace IntradosMediator;

int main(){
    IntradosMediator::addVehicle("Car X");
    return 0;
}

错误是:

Test.obj : error LNK2019: unresolved external symbol "public: static class Mapper *
 __cdecl Mapper::getInstance(void)" (?getInstance@Mapper@@SAPAV1@XZ) referenced in
function "void __cdecl IntradosMediator::addVehicle(class std::basic_string<char,struct
std::char_traits<char>,class std::allocator<char> >)"
(?addVehicle@IntradosMediator@@YAXV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@
std@@@Z)

我确保将Intrados添加为Test的引用，并且还将其包括在Include Directories中。由于我是C++的新手，所以不确定在这里做什么。在此先感谢您的任何建议。

编辑:
我在这里添加Mapper代码:

//.h
#ifndef MAPPER_H
#define MAPPER_H
#include <string>
using std::string;

class Mapper {
public:
    static Mapper* getInstance();
    void addVehicle(string);
private:
    //this is a singleton
    Mapper(){};
};
#endif

//.cpp
#include "Mapper.h"
#include <vector>
#include <iostream>
#include <string>
using namespace std;


vector<string> vehicleList;

Mapper* Mapper::getInstance(){
    static Mapper instance;
    return &instance;
}

void
Mapper::addVehicle(string vehicleName) {
    vehicleList.push_back(vehicleName);
}

最佳答案

该错误表明链接器找不到Mapper::getInstance(似乎找到了addVehicle函数就好了)。您是否可能未在链接中包含实现“Mapper”的库？

关于c++ - C++ “unresolved external symbol”使用来自不同项目的 namespace ，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/15537255/