未定義的引用class :: function

Question

我一直在爲uni和空閒時間做C編程，我正在轉向使用C++，並試圖從單獨的文件和類中開始，但是我遇到了一些問題當試圖做我的項目。我使用下面的Makefile

EXEC = main 
OBJS = main.o Bunny.o Name.o Board.o 
CC = g++ 

CFLAGS = -Wall -Wextra -Werror 
LIBS = 
LDFLAGS = 


$(EXEC): $(OBJS) 
    $(CC) $(LDFLAGS) -o $@ $(OBJS) $(LIBS) 



.PHONY: clean 

clean: 
    rm -f $(EXEC) $(OBJS) 
run: 
    ./$(EXEC) 

這是我的C一隻是改變的版本，所以它可能是，這裏有相關的其他文件

的main.cpp

#include <iostream> 

#include "Name.hpp" 
#include "definitions.hpp" 

int main() { 

    Name nameContainer; 

    nameContainer.initMaleNameValidArray(); 

    std::cout << "Got to just before the return!\n" << std::endl; 

    return 0; 
} 

Name.cpp

#include <iostream> 
#include <fstream> 
#include <string> 
#include "definitions.hpp" 

class Name{ 
    public: 
     void initFemaleNameArray() { 
      std::ifstream myReadFile; 
      myReadFile.open("girlsnames.txt"); 
      char output[100]; 
      if (myReadFile.is_open()) { 
       while (!myReadFile.eof()) { 
        myReadFile >> output; 
        std::cout<<output; 
       } 
      } 
      myReadFile.close(); 
     } 

     void initMaleNameArray() { 

     } 

     void initFemaleNameValidArray() { 
      static int femaleValidArray[GIRLS_NAMES] = {0}; 
     } 

     void initMaleNameValidArray() { 
      static int MaleValidArray[GIRLS_NAMES] = {0}; 
     } 

     void freeAFemaleName(std::string name); 

     void freeAMaleName(std::string name); 

     std::string returnFreeFemaleName(); 

     std::string returnFreeMaleName(); 

    private: 
     std::string femaleNameArray[GIRLS_NAMES]; 

     std::string maleNameArray[BOYS_NAMES]; 

     int femaleValidArray[GIRLS_NAMES]; 

     int maleValidArray[BOYS_NAMES]; 
}; 

Name.hpp

#ifndef NAME_HPP 
#define NAME_HPP 

#include "definitions.hpp" 

class Name{ 
    public: 
     void initFemaleNameArray(); 

     void initMaleNameArray(); 

     void initFemaleNameValidArray(); 

     void initMaleNameValidArray(); 

     void freeAFemaleName(std::string name); 

     void freeAMaleName(std::string name); 

     std::string returnFreeFemaleName(); 

     std::string returnFreeMaleName(); 

    private: 
     std::string femaleNameArray[GIRLS_NAMES]; 

     std::string maleNameArray[BOYS_NAMES]; 

     int femaleValidArray[GIRLS_NAMES]; 

     int maleValidArray[BOYS_NAMES]; 
}; 

#endif 

和錯誤即時得到當運行make是：

mark@Mark-Linux:~/Documents/Misc/C++/Bunny$ make 
g++ -c -o main.o main.cpp 
g++ -c -o Bunny.o Bunny.cpp 
g++ -c -o Name.o Name.cpp 
g++ -c -o Board.o Board.cpp 
g++ -o main main.o Bunny.o Name.o Board.o 
main.o: In function `main': 
main.cpp:(.text+0x26): undefined reference to `Name::initFemaleNameArray()' 
collect2: ld returned 1 exit status 
make: *** [main] Error 1 

目前，我只是想看看我是否能在不同的文件，因此不完全使用的方法從一個類碼。

對不起，關於牆的文字，但我很好，真的難住，所以如果任何人可以提供任何意見，將不勝感激。

Answer 1

您的Name.cpp和Name.hpp實際上聲明瞭單獨的類，這可能是未定義的行爲。相反，你應該Name.cpp是這樣的：

#include <iostream> 
#include <fstream> 
#include <string> 
#include "Name.hpp" 

void Name::initFemaleNameArray() { 
    std::ifstream myReadFile; 

等

Answer 2

在name.hpp您所定義的名稱類，這是確定的。但是在name.cpp中，您正在再次定義該類。這不是你想要的。你應該有name.cpp實現這些功能。這將是這個樣子：

#include <iostream> 
#include <fstream> 
#include <string> 
#include "definitions.hpp" 

#include "name.hpp" 

void Name::initFemaleNameArray() { 
    std::ifstream myReadFile; 
    myReadFile.open("girlsnames.txt"); 
    char output[100]; 
    if (myReadFile.is_open()) { 
     while (!myReadFile.eof()) { 
      myReadFile >> output; 
      std::cout<<output; 
     } 
    } 
    myReadFile.close(); 
} 

void Name::initMaleNameArray() {} 

void Name::initFemaleNameValidArray() { 
    // This is wrong, too. This creates a new array 
    //static int femaleValidArray[GIRLS_NAMES] = {0}; 
    // You want this: 
    memset(femaleValidArray, 0, sizeof(femaleValidArray)); 
} 

void Name::initMaleNameValidArray() { 
    //static int MaleValidArray[GIRLS_NAMES] = {0}; 
    memset(MaleValidArray, 0, sizeof(MaleValidArray)); 
} 

void Name::freeAFemaleName(std::string name) {} 
void Name::freeAMaleName(std::string name) {} 
std::string Name::returnFreeFemaleName() {} 
std::string Name::returnFreeMaleName() {}