Read info from a txt file into a class

[crimsonzero2]

Hello, I'm having trouble in getting my program to read from a file and put all the proper data into its proper class variables. I have a class (called Champion) that has string variable for a name and a vector of strings for items. I also have a vector of Champion that holds multiple champions. Any help would be appreciated. Here's my code:

Champion.hpp

#ifndef CHAMPION_HPP_INCLUDED
#define CHAMPION_HPP_INCLUDED

#include <iostream>
#include <string>
#include <vector>

using namespace std;

class Champion
{
    private:
        string name;
        vector<string> items;
    public:
        Champion();
        Champion(string name);
        void addItems();
        void editItem();
        string getItem(int item_num);
        int numOfItems();
        string getName();
        ~Champion();
};

ostream &operator <<(ostream &stream, Champion &c); //function to print out all class data
//istream &operator >>(istream &stream, Champion &c);   //not needed so far

#endif // CHAMPION_HPP_INCLUDED

Champion.cpp

#include <iostream>
#include <string>
#include <vector>

#include "Champion.hpp"

using namespace std;

Champion::Champion()
{
    this->name = "";
}

Champion::Champion(string name)
{
    this->name = name;
}

void Champion::addItems()
{
    string item;

    cout << "item 1: ";
    getline(cin, item);
    items.push_back(item);

    cout << "item 2: ";
    getline(cin, item);
    items.push_back(item);

    cout << "item 3: ";
    getline(cin, item);
    items.push_back(item);

    cout << "item 4: ";
    getline(cin, item);
    items.push_back(item);

    cout << "item 5: ";
    getline(cin, item);
    items.push_back(item);

    cout << "item 6: ";
    getline(cin, item);
    items.push_back(item);
}

void Champion::editItem()
{
    int item_num;
    string item;
    //vector<string>::iterator it;
    cout << "Which item do you want to change? ";
    cin >> item_num;
    bool item_set = false;
    while(!item_set)
    {
        switch(item_num)
        {
            //make sure its a proper item slot
            case 1:
            case 2:
            case 3:
            case 4:
            case 5:
            case 6:
                cout << "Enter new item name: ";
                cin.ignore();
                getline(cin, item);
                this->items[item_num - 1] = item; //set new item
                item_set = true;
                break;
            default:
                cout << "Invalid number.  Try again." << endl;
                break;
        }
    }
}

string Champion::getItem(int item_num)
{
    return this->items[item_num];
}

int Champion::numOfItems()
{
    return this->items.size();
}

string Champion::getName()
{
    return this->name;
}

Champion::~Champion()
{

}

ostream &operator <<(ostream &stream, Champion &c)
{
    stream << c.getName();
    stream << endl;
    for(int i = 0; i < c.numOfItems(); i++)
    {
        stream << c.getItem(i);
        stream << endl;
    }
    return stream;
    /*stream << c.getItem(1);
    return stream;*/ //test
}

main.cpp

#include <iostream>
#include <string>
#include <vector>
#include <fstream>

#include "Champion.hpp"

using namespace std;

enum {ADD_CHAMPION = 1, EDIT_ITEM = 2, PRINT_LIST = 3, SAVE = 4, LOAD = 5, HELP = 6, QUIT = 7};

int main()
{
    vector<Champion> champions;
    int option;
    string name;
    cout << "Select an option: ";
    cin >> option;
    while(option != QUIT)
    {
        switch(option)
        {
            case ADD_CHAMPION:
                {
                    cout << "Enter champion name: ";
                    cin >> name;
                    int i;
                    for(i = 0; i < (int)champions.size(); i++)
                    {
                        if(champions[i].getName() == name)
                        {
                            cout << "Champion already exist." << endl;
                            break;
                        }
                    }
                    if(i == (int)champions.size())
                    {
                        Champion a(name);
                        cin.ignore();   //ignores name so addItems() would not add it
                        a.addItems();
                        champions.push_back(a);
                    }
                    break;
                }
            case EDIT_ITEM:
                {
                    cout << "Enter champion name: ";
                    cin >> name;
                    for(int i = 0; i < (int)champions.size(); i++)
                    {
                        if(champions[i].getName() == name)
                        {
                            champions[i].editItem();
                            break;
                        }
                    }
                }
                break;
            case PRINT_LIST:
                {
                    for(int i = 0; i < (int)champions.size(); i++)
                    {
                        cout << champions[i] << endl;
                    }
                    break;
                }
            case SAVE:
                {
                    ofstream ofs;
                    ofs.open("LoL.txt", ios::trunc);    //overwrite old file
                    if(ofs.is_open())
                    {
                        for(int i = 0; i < (int) champions.size(); i++)
                        {
                            ofs << champions[i] << endl;
                        }
                        ofs << endl;
                        ofs.close();
                    }
                    else
                    {
                        cout << "Fail to open file." << endl;
                    }
                    break;
                }
            case LOAD:
                {
                    ifstream ifs;
                    string line;
                    ifs.open("LoL.txt");
                    if(ifs.is_open())
                    {
                        while(getline(ifs, line))
                        {
                            //stuck here on how to add input into proper variables in class Champion
                        }
                        ifs.close();
                    }
                    else
                    {
                        cout << "Fail to open file." << endl;
                    }
                    break;
                }
            case HELP:
            default:
                {
                    cout << "Invalid option." << endl;
                    break;
                }
        }
        cout << "Select an option: ";
        cin >> option;
    }

    return 0;
}

[AbstractionAnon]

In looking at your save routine, the problem I see is that you don't write a delimiter between each champion (or a count of how many items each champion has). This makes it impossible to determine where one champion's data ends and the next one starts.

Lines 94-96: You want to read the champion's name first, then you want to loop reading that champion's items until you either encounter a delimiter, or reach the number of items that champion has.

I would suggest adding at line 103 of champion.cpp:

   stream << c.numOfItems() << endl;

Then on load, after reading the champion's name, read the number of items from the file, then loop reading items for that number of times.

[crimsonzero2]

Ok, that will work. Thank you :)

[AbstractionAnon]

I should have suggested this before.

You have already overloaded the << operator to write a champion to an output stream. Why not overload the >> operator to read a champion from an input stream.

Lines 93-97 become simply:

    Champion  champ;  // temp instance used for reading
    while (ifs >> champ)
        champions.push_back (champ); 
    ifs.close();

This encapsulates the code for reading a champion into it's class where it belongs. This does not address the delimiter/count issue, but it isolates it to code in your class. If you decide to add additional variables to champion, only your input and output overloads needs to change.