Parsing CSV into Struct Array - c++

Question

I am trying to parse CSV into Array of structures. Delimiter is ';'. If you look into the code it seems that I filled only first element of the array out of nine that is 9 lines are in my CSV right now. Remaining elements of the array are just 0. Anyone got some advice? Thanks
fileTO.open("imput.csv", ios_base :: app);
fileFROM.open("imput.csv", ios_base :: app);
//IntoCsvThruConsole();
// array of structures from csv
string line;
string sID, stype, scategory, samount, sdate;
int lines = CountExistingLines();
Properties * structure = new Properties[lines];
int counter = 0;
int position = 0;
while (getline(fileFROM, line))
{
sID = "";
samount = "";
for (int i = 0; i < line.size(); i++)
{
if (line[i] == ';')
{
position++;
continue;
}
switch (position)
{
case 0 : sID = sID + line[i];
break;
case 1 : structure[counter].type = structure[counter].type + line[i];
break;
case 2 : structure[counter].category = structure[counter].category + line[i];
break;
case 3 : samount = samount + line[i];
break;
case 4 : structure[counter].date = structure[counter].date + line[i];
break;
}
}
structure[counter].ID = atoi(sID.c_str());
structure[counter].amount = atoi(samount.c_str());
cout << "ID zaznamu: " << structure[counter].ID << endl;
cout << "Typ: " << structure[counter].type << endl;
cout << "Kategorie: " << structure[counter].category << endl;
cout << "Castka: " << structure[counter].amount << endl;
cout << "Datum: " << structure[counter].date << endl;
counter++;
}
delete[] structure;
I have globally initialized struct correctly and also fstreams. Hope it is enough. Thanks
enter image description here

Answer 1

I recommend using Boost.Spirit for such parsing tasks.
#include <iostream>
#include <sstream>
#include <string>
#include <vector>
#include <boost/fusion/adapted.hpp>
#include <boost/spirit/home/x3.hpp>
struct Date
{
int day;
int month;
int year;
};
std::ostream& operator<<(std::ostream& os, Date const &d)
{
os << d.day << '/' << d.month << '/' << d.year;
return os;
}
BOOST_FUSION_ADAPT_STRUCT(
Date,
day, month, year)
struct Properties
{
int ID;
std::string type;
std::string category;
int amount;
Date date;
};
BOOST_FUSION_ADAPT_STRUCT(
Properties,
ID, type, category, amount, date)
std::vector<Properties> parse(std::string const &input)
{
auto iter = input.begin();
using namespace boost::spirit::x3;
auto name = rule<class name, std::string>{}
= lexeme[alpha >> *alpha];
auto date = rule<class date, Date>{}
= int_ > '/' > int_ > '/' > int_;
std::vector<Properties> result;
bool r = phrase_parse(iter, input.end(),
(int_ > ';' > name > ';' > name > ';' > int_ > ';' > date) % eol,
space - eol, result);
if (!r)
{
std::string rest(iter, input.end());
throw std::invalid_argument("Parsing failed at " + rest);
}
return result;
}
int main()
{
// This could be a file instead with std::ifstream
std::istringstream input;
input.str(
"1;TypeA;CategoryA;10;05/12/2017\n"
"2;TypeB;CategoryA;21;04/12/2017\n"
"3;TypeB;CategoryB;19;01/12/2017\n"
"4;TypeA;CategoryA; 6;20/11/2017\n");
std::vector<Properties> entry = parse(input.str());
for (auto e : entry)
{
std::cout << "Found the following entries:\n"
<< " ID: " << e.ID << "\n"
<< " Type: " << e.type << "\n"
<< " Category: " << e.category << "\n"
<< " Amount: " << e.amount << "\n"
<< " Date: " << e.date << "\n";
}
}
Live example