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How to read data from a line in a .txt file into a structure in C++?

Suppose I have a Struct:

 struct  Game
{
    int id;
    int year;
    string title;
    string publisher;
    string developer;
};

Now I have a .txt file in which the content goes like this:

1 2012 FarCry Crytek Ubisoft

Now as I run the program I want the program to a new vector Game and set its values according to the data in that line in the external .txt file. Is that achievable? Any help would be appreciated. Here is my code so far:

#include "stdafx.h"
#include <iostream>
#include <fstream>
#include <string>
#include <vector>

using namespace std;


struct  Game

{
    int id;
    int year;
    string title;
    string publisher;
    string developer;
};

void ShowData(vector<Game> myDatabase)
{
        cout << endl;
        for(size_t i = 0; i <= myDatabase.size()-1; i++)
        {
            cout << endl;
            cout << "ITEM NO" << "[" << i + 1 << "]" <<endl;
            cout << "    TITLE: " << myDatabase[i].title << endl;
            cout << "     YEAR: " << myDatabase[i].year << endl;
            cout << "DEVELOPER: " << myDatabase[i].developer << endl;
            cout << "PUBLISHER: " << myDatabase[i].publisher << endl;
        }

}

int _tmain(int argc, _TCHAR* argv[])
{
    string option;
    int serialNumber = 0;
    int count = 0;
    char str[80];
    vector<Game> Database;

    fstream fout;
    fout.open("Database.txt");

    cout << endl;
repeat: 
    cout << endl;

    cout << "ADD | SHOW | DELETE | EDIT | SEARCH " << endl;

    cout << "SAY :  ";
    cin >> option;

    if(option == "ADD" || option == "Add" || option == "add")
    {
        serialNumber += 1;
        Game NewGame;
        NewGame.id = serialNumber;
        cout << endl << "Name: ";
        cin >> NewGame.title;
        cout << "Year: ";
        cin >> NewGame.year;
        cout << "Developer: ";
        cin >> NewGame.developer;
        cout << "Publisher: ";
        cin >> NewGame.publisher;
        cout << endl;

        Database.push_back(NewGame);
        cout << endl;
        cout << "Size is: " << Database.size();


        fout <<  serialNumber << " " << Database[Database.size() - 1].title << " " << Database[Database.size() - 1].year << " "<< Database[Database.size() - 1].developer << " " << Database[Database.size() - 1].publisher << endl;


        goto repeat;

    }
    if (option == "SHOW" || option == "Show" || option == "show")
    {
        ShowData(Database);
        goto repeat;
    }

    if(option == "DELETE" || option == "Delete" || option == "delete")
    {
        int choose;
        cout << "Delete Item No: ";
        cin >> choose;
        Database.erase(Database.begin() + (choose - 1));

        cout << endl;
        ShowData(Database);

        goto repeat;

    }
    if(option == "SEARCH" || option == "Search" || option == "search")
    {
        cout << "Search By [ID, TITLE, YEAR, DEVELOPER, PUBLISHER] : ";
        string choose;
        cin >> choose;
        if(choose == "ID" || choose == "Id" || choose == "id")
        {
            int idNumber;
            cout << "ID No: ";
            cin >> idNumber;
            cout << endl;
            cout << "ITEM NO" << "[" << idNumber << "]" <<endl;
            cout << "    TITLE: " << Database[idNumber - 1].title << endl;
            cout << "     YEAR: " << Database[idNumber - 1].year << endl;
            cout << "DEVELOPER: " << Database[idNumber - 1].developer << endl;
            cout << "PUBLISHER: " << Database[idNumber - 1].publisher << endl;

            goto repeat;
        }
        else if (choose == "TITLE" || choose == "Title" || choose == "title")
        {
            string whatTitle;
            cout << "Enter Title: ";
            cin >> whatTitle;

            for(size_t i = 0; i <= Database.size()-1; i++)
            {
                if(Database[i].title == whatTitle)
                {
                    cout << endl;
                    cout << "ITEM NO" << "[" << i + 1 << "]" <<endl;
                    cout << "    TITLE: " << Database[i].title << endl;
                    cout << "     YEAR: " << Database[i].year << endl;
                    cout << "DEVELOPER: " << Database[i].developer << endl;
                    cout << "PUBLISHER: " << Database[i].publisher << endl;
                }
            }
            goto repeat;
        }
        else if (choose == "YEAR" || choose == "Year" || choose == "year")
        {
            int whatYear;
            cout << "Enter Year: ";
            cin >> whatYear;

            for(size_t i = 0; i <= Database.size()-1; i++)
            {
                if(Database[i].year == whatYear)
                {
                    cout << endl;
                    cout << "ITEM NO" << "[" << i + 1 << "]" <<endl;
                    cout << "    TITLE: " << Database[i].title << endl;
                    cout << "     YEAR: " << Database[i].year << endl;
                    cout << "DEVELOPER: " << Database[i].developer << endl;
                    cout << "PUBLISHER: " << Database[i].publisher << endl;
                }
            }

            goto repeat;
        }
        else if (choose == "DEVELOPER" || choose == "Developer" || choose == "developer")
        {
            string whatDeveloper;
            cout << "Enter Developer Name: ";
            cin >> whatDeveloper;

            for(size_t i = 0; i <= Database.size()-1; i++)
            {
                if(Database[i].developer == whatDeveloper)
                {
                    cout << endl;
                    cout << "ITEM NO" << "[" << i + 1 << "]" <<endl;
                    cout << "    TITLE: " << Database[i].title << endl;
                    cout << "     YEAR: " << Database[i].year << endl;
                    cout << "DEVELOPER: " << Database[i].developer << endl;
                    cout << "PUBLISHER: " << Database[i].publisher << endl;
                }
            }
            goto repeat;
        }
        else if (choose == "PUBLISHER" || choose == "Publisher" || choose == "publisher")
        {
            string whatPublisher;
            cout << "Enter Publisher Name: ";
            cin >> whatPublisher;

            for(size_t i = 0; i <= Database.size()-1; i++)
            {
                if(Database[i].publisher == whatPublisher)
                {
                    cout << endl;
                    cout << "ITEM NO" << "[" << i + 1 << "]" <<endl;
                    cout << "    TITLE: " << Database[i].title << endl;
                    cout << "     YEAR: " << Database[i].year << endl;
                    cout << "DEVELOPER: " << Database[i].developer << endl;
                    cout << "PUBLISHER: " << Database[i].publisher << endl;
                }
            }
            goto repeat;
        }
    }
    if (option == "EDIT" || option == "Edit" || option == "edit")
    {
        int whichItem;

        cout << "Enter Item No: ";
        cin >> whichItem;

        cout << endl << "Name: ";
        string name;
        cin >> name;
        Database[whichItem - 1].title = name;
        cout << "Year: ";
        int year;
        cin >> year;
        Database[whichItem - 1].year = year;
        cout << "Developer: ";
        string developer;
        cin >> developer;
        Database[whichItem - 1].developer = developer;
        cout << "Publisher: ";
        string publisher;
        cin >> publisher;
        Database[whichItem - 1].publisher = publisher;
        cout << endl;

        ShowData(Database);

        goto repeat;
    }
    fout.close();   




    system("PAUSE");
    return 0;
}

What I am trying to do is, as I run the program it should get all the data from the text file and put them in their relative structures and then push each structure into a vector.

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1 Reply

0 votes
by (71.8m points)

Solution 1

  1. Read file line by line (you can use getline)
  2. Split the string using space character as delimiter here is an example
  3. Convert the split-ed tokens as required (like convert first token to int ). here is an example

Solution 2

If you have same number of tokens in each line (here 5), then each can be read individually

std::ifstream file(fileName);
struct Game game;
file >> game.id >> game.year>>game.title>>game.publisher>>game.developer;

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