As the title says, I am learning how to use pointers in C++. I have been tasked with writing a program that gets data about countries from a text file, loads them into an array of class objects, then lets the user view the data, remove an entry or quit.
I'm running into a problem with class accessor functions. I am getting the error 'variable not declared in scope.' I get what this error is trying to tell me, but I can't figure out how to get the accessors to function properly.
The requirements for the assignment are to use char-pointers to store strings, so I think that's adding an extra level of complexity. I want the accessor function to just return a single variable, e.g. country name, capital and surface area.
I am using CodeBlocks and running on Ubunutu. I have the compiler set to c++11.
Anyways, here is the code:
//This is the main.cpp file
#include <iostream>
#include <fstream>
#include <string>
#include <cstdlib>
#include "Country.h"
const int FILE_PATH_SZ = 512;
Country** g_countryArray;
int g_arrsz = 0;
using namespace std;
void openFile(ifstream& inFile, string pathName);
void getArrSize(ifstream& inFile, string pathName, string& countriesData);
void fillCountryArr(ifstream& inFile, string pathName, string& countryName, string& capitalName, string& tempSurfaceArea);
void printCountryData(Country** g_countryArray, int g_arrsz);
int main() {
char menuChoice, startingLetter;
string pathName, countriesData, countryName, capitalName, tempSurfaceArea;
ifstream inFile;
do {
cout << "Choose one of the following:" << endl << endl;
cout << "Menu options" << endl << endl;
cout << "a) Read a text file:" << endl;
cout << "b) Remove countries starting with given letter" << endl;
cout << "c) Print all data to console" << endl;
cout << "d) Quit" << endl;
cin >> menuChoice;
switch (menuChoice)
{
case 'a':
{
cout << "Please enter the full path name of the file you wish to open: " << endl;
cin >> pathName;
openFile(inFile, pathName);
getArrSize(inFile, pathName, countriesData);
fillCountryArr(inFile, pathName, countryName, capitalName, tempSurfaceArea);
}
case 'b':
{
cout << "Enter the starting letter: " << endl;
cin >> startingLetter;
toupper(startingLetter);
}
case 'c':
{
printCountryData(g_countryArray, g_arrsz);
}
}
}while (menuChoice != 'd');
return 0;
}
void openFile(ifstream& inFile, string pathName)
{
inFile.open(pathName.c_str());
if (!inFile)
{
cout << "Cannot open file." << endl;
}
inFile.close();
inFile.clear(std::ios_base::goodbit);
}
void getArrSize(ifstream& inFile, string pathName, string& countriesData)
{
inFile.open(pathName.c_str());
while (getline(inFile, countriesData))
{
++g_arrsz;
}
g_countryArray = new Country* [g_arrsz]; //declares g_countryArray to be an array of pointers of size [g_arrsz]. The array holds pointers to Country class objects
}
void fillCountryArr(ifstream& inFile, string pathName, string& countryName, string& capitalName, string& tempSurfaceArea)
{
long int surfaceArea;
//closes and reopens the file cleanly
inFile.close();
inFile.clear(std::ios_base::goodbit);
inFile.open(pathName.c_str());
for (int i = 0; i < g_arrsz; i++)
{
getline(inFile, countryName, ','); //gets the name of the country from the input file
getline(inFile, capitalName, ','); //gets the name of the capital of the country from the input file
getline(inFile, tempSurfaceArea); //gets the surface area of the country in the form of a string
surfaceArea = stol(tempSurfaceArea); //converts the string version of surface area to an integer
g_countryArray[i] = new Country(countryName.c_str(), capitalName.c_str(), surfaceArea); //creates new Country class and stores address in the i'th element of g_countryArray
} //passes the name of the country and capital of the country in to the constructor as
//c-strings and passes surfaceArea as an int
}
void printCountryData(Country** g_countryArray, int g_arrsz)
{
for (int i = 0; i < g_arrsz; ++i)
{
cout << g_countryArray[i]->GetCountryName() << ", ";
cout << g_countryArray[i]->GetCapital() << ", ";
cout << g_countryArray[i]->GetSurfaceArea() << endl;
}
}
The function just above here printCountryData is where I want to pass the array of class objects and array size variables, then call the accessor functions.
//here is the Country.h file
#include <iostream>
#include <string>
#include <cstring>
using namespace std;
class Country
{
private:
char* name_;
char* capital_;
long surfaceArea_;
public:
Country (const char* country, const char* capital, long surfaceArea);
~Country ();
char* GetCountryName();
char* GetCapital();
long GetSurfaceArea();
};
Country::Country(const char* country, const char* capital, long surfaceArea)
{
int countryLen, capitalLen; //variables to store length of c-strings country and capital for dynamically allocating arrays of the right length
countryLen = strlen(country); //gets length of country name
capitalLen = strlen(capital); //gets length of capital name
name_ = new char[countryLen + 1]; //dyanmically creates a new character array of size countryLen and stores base address of array in name_ pointer
for (int i = 0; i < countryLen; i++)//transfers storage of country name to the name_ array
{
name_[i] = country[i];
}
capital_ = new char[capitalLen + 1]; //creates a new character array of size capitalLen and stores base address of array in capital_ pointer
for (int i = 0; i < countryLen; i++)
{
capital_[i] = capital[i];
}
surfaceArea_ = surfaceArea;
}
char* GetCountryName()
{
return name_;
}
char* GetCapital()
{
return capital_;
}
long GetSurfaceArea()
{
return surfaceArea_;
}
It's these 3 accessor functions at the bottom that are generating the error 'name_ is not declared in this scope, etc.'
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