Structures and File input questions

[Slee]

So basically, I have no idea. I can't get getline to work for the structure and I've been trying for hours upon hours. I'm also using a function. Any help would be appreciated.

  void studentRegistration(Values info[MAX_STUDENT], int size)
{
	ifstream inFile; //needed to open file and read
	inFile.open("student.txt");
	if (!inFile.fail())
	{
		for (int i = 0; i < 11; i++)
		{
			getline(inFile, info[i].ID);
			
                 }
		
                 inFile.close();
		cout << "Done.\n";
	}
}

My structure looks like this:

struct Values 
{
	int ID;
	char name;
	char answer_choice; 
};

My text file looks like this:

ID number, name, answer

[fiji885]

You're using getline on an int. You can only use getline on strings. Also you need to read info by info... Your for loop should have at least 3 states, depending on how you program it.

for(int i = 0; i << 1; i++)
{
    // read in type_int memberID
    // read in name
    // read in answer_choice
}

[Slee]

Well I changed the name to a string but i'm still getting an error

ifstream inFile; //needed to open file and read
	inFile.open("student.txt");
	if (!inFile.fail())
	{
		
                for (int i = 0; i < 11; i++)
		{
		    inFile >> info[i].ID;	
                    inFile.getline(info[i].name, 50, '\n');
                    inFile.getline(info[i].answer_choice, 1, 'n');
			
                 }
		
                 inFile.close();
		cout << "Done.\n";
	}

I'm also using char for answer_choice. I keep getting "no instance of overload function"

[Chervil]

ID number, name, answer

That still leaves room for uncertainty, I can't be sure whether the ID is an integer or maybe contains other characters. name must be a string, not a single character. answer could be anything, an integer, a character, a string of several words.

Given that your struct had char name; which doesn't make sense, it is quite likely that the other parts may be wrong or less than optimal too.


Assuming that only the name is a string, maybe do it like this. Here I read the file one line at a time, then extract the details from that line. A stringstream is used to do that. Also I passed the size by reference, to hold the actual number of records read from the file.

#include <iostream>
#include <string>
#include <fstream>
#include <sstream>
#include <iomanip>

using namespace std;

struct Values 
{
	int ID;
	string name;
	char answer_choice; 
};

const int MAX_STUDENT = 100;

void studentRegistration(Values info[MAX_STUDENT], int & size)
{
    ifstream inFile("student.txt");
    if (!inFile)
    {
        cout << "file could not be opened\n";
        return;
    }
    
    size = 0;
    string line;

    while (size < MAX_STUDENT && getline(inFile, line))
    {
        // use a stringstream to parse the contents of each line
        istringstream ss(line);
        char comma; 
        ss >> info[size].ID >> comma;
        getline(ss, info[size].name, ',');
        ss >> info[size].answer_choice;

        if (ss) // if stream input did not fail
            ++size;
    }
    
}

int main()
{

    Values student_data[MAX_STUDENT];
    int count = 0;
    studentRegistration(student_data, count);  
    
    for (int i=0; i<count; ++i)
    {
        cout << setw(10) << student_data[i].ID
             << setw(20) << student_data[i].name
             << setw(10) << student_data[i].answer_choice << '\n';
    }
    
}