C++ read line to class vector - c++

Question

I have next c++ class called "Contact":
class Contact
{
private:
std::string contactName;
double subscriptionPrice;
int minutesIncluded;
public:
Contact(const std::string &contactName, double subscriptionPrice,
int minutesIncluded) : contactName(contactName), subscriptionPrice(subscriptionPrice), minutesIncluded(minutesIncluded)) {}
Contact() {
}
...gettetrs and setters
}
I have text file with one or more contacts in format:
asd,1.00000,1
In main method I have method that add properly vector of contacts in this text file. Problem is when I try to read from it. My target is to convert text file into vector of contacts. Method I use is next:
void phonebook_load(vector<Contact> &contacts)
{
string line;
ifstream phonebook_file;
vector<std::string> lines;
phonebook_file.open(phonebook_filename);
if(!phonebook_file.is_open())
cout << "Phonebook file could not be openned !!!" << endl;
else
{
while (phonebook_file.good())
{
for (string line; getline(phonebook_file, line, ','); )
lines.push_back(line);
}
phonebook_file.close();
}
}
I have two options:
Read line by line (which I cannot split by ",")
Split by "," which print every property of contact on new line, and I don't see how tho handle it from there.
What should I change in my method in order to read file line by line and properly convert it to vector<Contact>

Answer 1

Provide stream extraction and stream insertion operators for your type:
#include <string>
#include <vector>
#include <iterator>
#include <fstream>
#include <iostream>
class Contact
{
private:
std::string contactName;
double subscriptionPrice;
int minutesIncluded;
public:
Contact() {}
Contact(const std::string &contactName, double subscriptionPrice, int minutesIncluded)
: contactName { contactName },
subscriptionPrice { subscriptionPrice },
minutesIncluded { minutesIncluded }
{}
// declare the stream extraction and stream insertion operators as firends
// of your class to give them direct access to members without the need for
// getter and setter functions.
friend std::istream& operator>>(std::istream &is, Contact &contact);
friend std::ostream& operator<<(std::ostream &os, Contact const &contact);
};
std::istream& operator>>(std::istream &is, Contact &contact)
{
std::string contact_name;
if (!std::getline(is, contact_name, ',')) // use getline with a delimiter
return is; // to allow whitespace in names
// which >> doesn't
char seperator;
double subscription_price;
int minutes_included;
if (!(is >> subscription_price >> seperator >> minutes_included) || seperator != ',') {
is.setstate(std::ios::failbit);
return is;
}
contact = Contact{ contact_name, subscription_price, minutes_included };
return is;
}
std::ostream& operator<<(std::ostream &os, Contact const &contact)
{
os << contact.contactName << ", " << std::fixed << contact.subscriptionPrice
<< ", " << contact.minutesIncluded;
return os;
}
int main()
{
std::ifstream is{ "test.txt" };
std::vector<Contact> contacts{ std::istream_iterator<Contact>{ is },
std::istream_iterator<Contact>{} };
for (auto const &c : contacts)
std::cout << c << '\n';
}