Trouble reading from text file into array using pointers

[apeachaday]

I'm having a problem figuring out how to read the information from a text file and populate an array of structs using a pointer. My file and struct has 3 parts: account number, account name, and the amount in that account. I'm getting an error I don't know how to fix. This really should be easy, but I'm just missing it somewhere. I greatly appreciate any help, tips, or comments!

error:  Line 59:  invalid types 'budget [15][budget*]' for array subscrpt 

struct budget
{
    int budget_num;
    string name;
    float budget_value;
};

int main()
{
    budget ary[15];
    budget *ptr;

    ptr = &ary[0];

    //Open inFile
    inFile.open("ledger.dat");

    while(!inFile)
    {
        cout << "Error opening the inFile." << endl;
        return 1;
    }

    while(!inFile.eof())
    {
        for(ptr = &ary[0]; ptr < &ary[15]; ptr++)
        {
            *ptr = getline(inFile, ary[ptr]); //Line 59
        }
    }

    //Close the files
    inFile.close();

    //Exit program
    return EXIT_SUCCESS;
}

I have also tried the following code and get a different error.

    while(!inFile.eof())
    {
        for(ptr = &company[0]; ptr < &company[15]; ptr++)
        {
        getline(cin, ptr.budget_num, ptr.name, ptr.budget_value);
        }
    }

error:  request for member 'budget_num' in 'ptr', which is of non-class type 'budget*'

[EddieV223]

If the last error you are using . notation on a pointer. To access the object pointed to you need ptr->. Or (*ptr).

*ptr = getline(inFile, ary[ptr]); //Line 59

Is incorrect because you used a pointer in []. This should be a number for the index you wish to access.

And when you fix that problem you will have another. You're using a function that gets a std::string from a stream. But you put in one of your budgets in the function where the string should be.
getline(stream,string)

[apeachaday]

Ok, I'm really confused. :(

[Zephilinox]

in order to access what the ptr points to, you need to dereference it, (*ptr) would be what the ptr points to.

if you do ptr->name, it is the same as doing (*ptr).name, which is the same as doing budget.name, but doing ptr.name is illegal, ptr is simply a memory address, it has no member variables.

[apeachaday]

I changed the code, but now I'm getting a different error.

error: no matching function for call to 'getline(std::ifstream&, int&, std::string&, float&)

    while(!inFile.eof())
    {
        for(ptr = &company[0]; ptr < &company[15]; ptr++)
        {
        getline(inFile, (*ptr).budget_num, (*ptr).name, (*ptr).budget_value);
        }
    }

[Zephilinox]

check the documentation on this website for the function "getline", see what arguments it accepts and how many.

[EddieV223]

Your use of getline is not what that function is for, and the arguments don't match, you can't do what your trying to do with getline. You need to get a std::string using getline, then parse the string yourself.

[apeachaday]

Ok, I changed my code and it doesn't give any errors, but I can't get it to print it out what is in there.

    while(!inFile.eof())
    {
        for(ptr = &company[0]; ptr < &company[SIZE]; ptr++)
        {
        //getline(inFile, (*ptr).budget_num, (*ptr).name, (*ptr).budget_value);
        cin >> (*ptr).budget_num;
        cin >> (*ptr).name;
        cin >> (*ptr).budget_value;
        }
    }

[EddieV223]

after every call to cin >> use a cin.ignore().

Also you have while (!inFile.eof() ) this loop either never runs or never ends depending on the file.

#include <string>
#include <iostream>
#define SIZE 3
using namespace std;

struct budget
{
int budget_num;
string name;
float budget_value;
};

int main()
    {

    budget company[SIZE];
    for ( int i = 0; i < SIZE; ++i )
        {
        cin >> company[i].budget_num;
        cin.ignore();
        getline(cin, company[i].name);
        cin >> company[i].budget_value;
        cin.ignore();
        }

    for ( int i = 0; i < SIZE; ++i )
        {
        cout << company[i].budget_num << ' ' << company[i].name << ' ' << company[i].budget_value << '\n';
        }
    std::cin.get();
    }

You should think of adding error checking to the cin >> lines. If you enter something invalid it will do undefined behavior.

[apeachaday]

I tried two different ways of doing this and I get the same junk out for both:

Number: 4669840
Name:   
Value:  3.76441e-039

Number: 4218308
Name:   
Value:  6.52879e-039

Number: 2686408
Name:   
Value:  6.52879e-039

Number: 0
Name:   
Value:  6.52879e-039

Number: 0
Name:   
Value:  8.40779e-045

Number: 4692468
Name:   
Value:  5.88904e-039

Number: 4639716
Name:   
Value:  0

Number: 0
Name:   
Value:  5.98096e-039

Number: 4659100
Name:   
Value:  8.40779e-045

Number: 4659100
Name:   
Value:  6.5271e-039

Number: 4692468
Name:   
Value:  3.76451e-039

Number: 4657896
Name:   
Value:  6.57555e-039

Number: 6
Name:   
Value:  8.40779e-045

Number: 16
Name:   
Value:  5.88904e-039

Number: 4642264
Name:   
Value:  0

    while(!inFile)
    {
//Same output for this:
        for(ptr = &company[0]; ptr < &company[SIZE]; ptr++)
        {
            cin >> (*ptr).budget_num;
            cin >> (*ptr).name;
            cin >> (*ptr).budget_value;
        }
//As output for this:
//        for ( int i = 0; i < SIZE; ++i )
//        {
//            cin >> (company[i].budget_num);
//            cin.ignore();
//            getline(cin, company[i].name);
//            cin >> company[i].budget_value;
//            cin.ignore();
//        }

    }

    for(int i = 0; i < SIZE; i++)
    {
    cout << "Number: " << company[i].budget_num << endl;
    cout << "Name:   " << company[i].name << endl;
    cout << "Value:  " << company[i].budget_value << endl;
    cout << endl;

    outFile << "Number: " << company[i].budget_num << endl;
    outFile << "Name:   " << company[i].name << endl;
    outFile << "Value:  " << company[i].budget_value << endl;
    outFile << endl;
    }