我非常感谢我对项目可能出错的一些建议。
我正在尝试编译我的项目，但我收到以下错误：
phoneBook.obj : error LNK2001: unresolved external symbol "private: static class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > * phoneBook::lastName" (?lastName@phoneBook@@0PAV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@A)
phoneBook.obj : error LNK2001: unresolved external symbol "private: static class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > * phoneBook::firstName" (?firstName@phoneBook@@0PAV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@A)
phoneBook.obj : error LNK2001: unresolved external symbol "private: static int * phoneBook::phone" (?phone@phoneBook@@0PAHA)
phoneBook.obj : error LNK2001: unresolved external symbol "private: static char (* phoneBook::dateOfBirth)[10]" (?dateOfBirth@phoneBook@@0PAY09DA)
这是头文件：
//phoneBook.h header file
#ifndef PHONEBOOK_H
#define PHONEBOOK_H
#include <string>
using namespace std;
class phoneBook
{
public:
phoneBook(); //default constructor
phoneBook(string lastN[], string firstN[],
int phoneNumber[], char date[][10]); //overloaded constructor
void setLastName(string lastN, int idNum); //sets last name for a given ID number,
//-IDs range from 1 to 50
void setFirstName(string firstN, int idNum); //sets first name for a given ID number
void setPhoneNumber(int phoneNum, int idNum); //sets the phone number for a given ID number
void setDate(char dateOB[], int idNum); //sets the date of birth for a given ID number
void loadFromFile(char fileName[]); //loads phone book data from a local file
int getPhoneNumber(string lastN, string firstN);//returns phone number for particular person
void getDOB(string lastN, string firstN, char testDOB[]); //sets date of birth for a particular person to testDOB array
void printPhone_DOB(string lastN, string firstN); //print phone number and date of birth
//-for a given person
void printNamesForDOB(char month[]); //print names of people with birthdays on given numeric month
void saveData(); //save data back to the local file
private:
string filename;
static string lastName[50];
static string firstName[50];
static int phone[50];
static char dateOfBirth[50][10];
};
#endif
实施档案：
//phoneBook.cpp implementation file
#include "phoneBook.h"
#include <iostream>
#include <string>
#include <fstream>
using namespace std;
//default constructor
phoneBook::phoneBook()
{
//declare variables
int i, j;
string lastName[50];
string firstName[50];
int phone[50];
char dateOfBirth[50][10];
//set variables to zero/null
filename = "";
for(i=0; i<50; i++)
{
lastName[i] = "";
firstName[i] = "";
phone[i] = 0;
//set date to zero, in format 00/00/0000
for(j=0; j<10; j++)
{
dateOfBirth[i][j] = '0';
if(j==2 || j==5)
dateOfBirth[i][j] = '/';
}
}
}
//overloaded constructor
phoneBook::phoneBook(std::string lastN[], std::string firstN[], int phoneNumber[], char date[][10])
{
//declare variables
int i, j;
string lastName[50];
string firstName[50];
int phone[50];
char dateOfBirth[50][10];
//set variables to zero/null
filename = "";
for(i=0; i<50; i++)
{
lastName[i] = lastN[i];
firstName[i] = firstN[i];
phone[i] = phoneNumber[i];
for(j=0; j<10; j++)
dateOfBirth[i][j] = date[i][j];
}
}
//setLastName function, sets the last name for a given ID number
void phoneBook::setLastName(string lastN, int idNum)
{
lastName[idNum-1] = lastN;
}
//setFirstName function, sets the first name for a given ID number
void phoneBook::setFirstName(string firstN, int idNum)
{
firstName[idNum-1] = firstN;
}
//setPhoneNumber function, sets the phone number for a given ID number
void phoneBook::setPhoneNumber(int phoneNum, int idNum)
{
phone[idNum-1] = phoneNum;
}
//setDate function, sets the date of birth for a given ID number
void phoneBook::setDate(char dateOB[], int idNum)
{
//declare variables
int i;
//set DOB
for(i=0; i<10; i++)
dateOfBirth[idNum][i] = dateOB[i];
}
//loadFromFile function, loads phone book data from a local file
void phoneBook::loadFromFile(char fileName[])
{
/*
**Assuming the following data in the text file:
**LastName FirstName PhoneNumber DateOfBirth
**(repeating 50 times)
*/
//setting local variable
filename = fileName;
//declaring variables
int i, j;
//opening file
ifstream file (filename.c_str());
//getting the data and copying it to local variables
while( file.good() )
{
for(i=0; i<50; i++)
{
file >> lastName[i];
file >> firstName[i];
file >> phone[i];
for(j=0; j<10; j++)
file >> dateOfBirth[i][j];
file.ignore(100, '\n');
}
}
//closing file
file.close();
}
//getPhoneNumber function, returns phone number for particular person
int phoneBook::getPhoneNumber(string lastN, string firstN)
{
//declaring variables
int i;
int index;
int phoneNum;
//finding matching first name, last name and its index
for(i=0; i<50; i++)
{
if(lastName[i] == lastN && firstName[i] == firstN)
index = i;
}
//returning phone number for matching name
phoneNum = phone[index];
return phoneNum;
}
//getDOB function, returns date of birth for a particular person
void phoneBook::getDOB(std::string lastN, std::string firstN, char testDOB[])
{
//declaring variables
int i;
int index;
//finding matching first name, last name and its index
for(i=0; i<50; i++)
{
if(lastName[i] == lastN && firstName[i] == firstN)
index = i;
}
//sets the char array which was passed by reference to the date
//of birth of the matched index
for(i=0; i<11; i++)
testDOB[i] = dateOfBirth[index][i];
}
//printPhone_DOB function, prints phone number and date of birth for a
//given person
void phoneBook::printPhone_DOB(std::string lastN, std::string firstN)
{
//declaring variables
int i;
int index;
//finding matching first name, last name and its index
for(i=0; i<50; i++)
{
if(lastName[i] == lastN && firstName[i] == firstN)
index = i;
}
//printing phone number and date of birth
cout << "Phone number: " << phone[index] << endl;
cout << "Date of birth: ";
for(i=0; i<10; i++)
cout << dateOfBirth[index][i];
cout << endl;
}
//printNamesForDOB function, print names of people with birthdays on
//given month
void phoneBook::printNamesForDOB(char month[])
{
//declaring variables
int i;
//printing names of people with birthdays in given month
cout << "The folowing people have birthdays in month number " << month << ":" << endl;
for(i=0; i<50; i++)
{
if(dateOfBirth[i][3] == month[0] && dateOfBirth[i][4] == month[1])
{
cout << "Last name: " << lastName[i] << endl;;
cout << "First Name: " << firstName[i] << endl;
cout << endl;
}
}
}
//saveData function, save data back to the local file
void phoneBook::saveData()
{
/*
**Assuming the following data scheme will be put:
**LastName FirstName PhoneNumber DateOfBirth
**(repeating 50 times)
*/
//opening file, deleting its contents
fstream file (filename.c_str(), fstream::out | fstream::trunc);
//declaring variables
int i, j;
//re-writting new data to file
for(i=0; i<50; i++)
{
file << lastName[i];
file << " ";
file << firstName[i];
file << " ";
file << phone[i];
file << " ";
for(j=0; j<10; j++)
file >> dateOfBirth[i][j];
file << " ";
file << endl; //end line
}
//closing file
file.close();
}
带主要功能的文件
//Problem 2.cpp
#include "phoneBook.h"
#include <iostream>
using namespace std;
int main()
{
return 0;
}
感谢您的时间。
答案 0 :(得分：3)
您已声明static个班级的phoneBook个成员，但您尚未提供这些成员的定义。
您需要在.cpp文件中提供如下定义：
string phoneBook::lastName[50];
string phoneBook::lastName[50];
string phoneBook::firstName[50];
int phoneBook::phone[50];
char phoneBook::dateOfBirth[50][10];
我还注意到你的构造函数声明局部变量，其名称与那些成员变量相同。这可能不是你想要做的，因为局部变量一旦被声明的函数退出就会消失。