我有头文件list.h和item.h，它有我的类声明。如果我没有在main中声明我的类，就像这样：
#include <iostream>
#include <fstream>
#include <ctype.h>
#include <vector>
#include <string>
#include <iterator>
#include <algorithm>
#include <iomanip>
#include <sstream>
#include "item.h"
#include "list.h"
int main()
{
bool runAgain = true;
do
{
int userMenuSelection;
int userContinueSelection;
bool printAll = true; //print list w/ totals
std::string outputFileName;
std::ofstream ofs; //to output files
std::ifstream ifs; //to import files
std::cout << "Welcome. Please Enter a Number." << std::endl;
std::cout << "1 - Create (add) list" << std::endl;
std::cout << "2 - Add item to list" << std::endl;
std::cout << "3 - Remove item from list" << std::endl;
std::cout << "4 - Edit item" << std::endl;
std::cout << "5 - View list & total price" << std::endl;
std::cout << "6 - Save list to a file" << std::endl;
std::cout << "7- Import list from file" << std::endl;
std::cout << "8 - Quit program" << std::endl;
if (isdigit(userMenuSelection) == 0)
{
std::cout << "Please enter a number!" << std::endl;
}
else
{
switch (userMenuSelection)
{
case 1:
list.addList();
break;
case 2:
list.printLists(printAll);
break;
case 3:
list.addItem();
break;
case 4:
list.removeItem();
break;
case 5:
list.editItem();
break;
case 6:
std::cout << "File will be imported from import.txt in the current directory." << std::endl;
std::cout << "Import List files are formatted as such: " << std::endl;
std::cout << "Itemname-Price-Quantity" << std::endl;
std::cout << "Examples:" << std::endl;
std::cout << "Egg Whites-1.99-20" << std::endl;
std::cout << "Apples-0.25-10" << std::endl;
ifs.open("import.txt");
list.importList(ifs);
break;
case 7:
if (list.isEmpty() == true)
{
std::cout << "There are no lists to export because you have not added any yet!" << std::endl;
break;
}
else
{
std::cout << "What would you like the new file to be called?" << std::endl;
std::cin >> outputFileName;
ofs.open((outputFileName + ".txt").c_str()); //create text file with user entered name
list.exportList(ofs);
std::cout << "New text file with name " << outputFileName << " created in directory." << std::endl;
break;
}
case 8:
return 0;
default:
std::cout << "Enter valid integer from 1 to 8." << std::endl;
}
}
std::cout << "Would you like to keep running the program?" << std::endl;
std::cout << "Enter 1 for YES, 2 for NO" << std::endl;
std::cin >> userContinueSelection;
if (isdigit(userContinueSelection) == 0)
{
std::cout << "You did not enter a number." << std::endl;
std::cout << "Program will continue to run." << std::endl;
}
else
{
switch (userContinueSelection)
{
case 1:
break;
case 2:
runAgain = false;
break;
default:
std::cout << "You didn't enter a valid number." << std::endl;
std::cout << "Program will continue to run." << std::endl;
}
}
} while (runAgain);
return 0;
}
这是编译器提供的：
20% make
g++ -std=c++0x -Wall -g main.cpp list.cpp item.cpp -o Assignment2
main.cpp: In function ‘int main()’:
main.cpp:77: error: expected unqualified-id before ‘.’ token
main.cpp:80: error: expected unqualified-id before ‘.’ token
main.cpp:83: error: expected unqualified-id before ‘.’ token
main.cpp:86: error: expected unqualified-id before ‘.’ token
main.cpp:89: error: expected unqualified-id before ‘.’ token
main.cpp:99: error: expected unqualified-id before ‘.’ token
main.cpp:102: error: expected primary-expression before ‘.’ token
main.cpp:112: error: expected unqualified-id before ‘.’ token
main.cpp:53: warning: unused variable ‘printAll’
make: *** [Assignment2] Error 1
如果我包含类声明：
#include <iostream>
#include <fstream>
#include <ctype.h>
#include <vector>
#include <string>
#include <iterator>
#include <algorithm>
#include <iomanip>
#include <sstream>
#include "item.h"
#include "list.h"
class item
class list
int main()
{
编译器给出了这个错误：
21% make
g++ -std=c++0x -Wall -g main.cpp list.cpp item.cpp -o Assignment2
main.cpp:49: error: two or more data types in declaration of ‘main’
make: *** [Assignment2] Error 1
flip1 ~/ecampus162/Assignment2 22%
最后，如果我在声明后加上分号：
include <iostream>
#include <fstream>
#include <ctype.h>
#include <vector>
#include <string>
#include <iterator>
#include <algorithm>
#include <iomanip>
#include <sstream>
#include "item.h"
#include "list.h"
class item;
class list;
int main()
{
这是编译器提供的内容：
22% make
g++ -std=c++0x -Wall -g main.cpp list.cpp item.cpp -o Assignment2
main.cpp: In function ‘int main()’:
main.cpp:81: error: expected unqualified-id before ‘.’ token
main.cpp:84: error: expected unqualified-id before ‘.’ token
main.cpp:87: error: expected unqualified-id before ‘.’ token
main.cpp:90: error: expected unqualified-id before ‘.’ token
main.cpp:93: error: expected unqualified-id before ‘.’ token
main.cpp:103: error: expected unqualified-id before ‘.’ token
main.cpp:106: error: expected primary-expression before ‘.’ token
main.cpp:116: error: expected unqualified-id before ‘.’ token
main.cpp:57: warning: unused variable ‘printAll’
make: *** [Assignment2] Error 1
关于我做错的任何想法？感谢。