Implementing a class into a database program - c++

Question

So I am very new to C++ and I am having a hard time learning how too implement classes into a function I have. My prof isn't being helpful in any capacity and I am very lost.
So the jist of the program is to take a file "books.txt" where each line contains an author and a book in the following format: Douglas Adams, The Hitchhiker's Guide to the Galaxy
I am trying to get the function to populate an array with "Book" objects with the title and author data from the file. It takes 4 input arguments: a name of the file as a string, an array of "Book" objects, the number of "Book" objects stored in the array of Book, and the capacity of the library system (with a max of 200).
For each line in the file, I am supposed to instantiate a Book object, fill in the author and title data members (listed in the code below), and append the object to the array of "Book" objects and it will return the numbers of books in the system as an integer.
Here is my header file (Book.h):
#include <iostream>
#include <math.h>
#include <string>
#include <string.h>
#include <fstream>
#include <stdio.h>
#include <cctype>
#include <locale>
#include <algorithm>
using namespace std;
#ifndef BOOK_H
#define BOOK_H
class Book{
private: //Member Variables
string author;
string title;
string inauthor;
string intitle;
string input;
string input2;
public:
Book();
Book(string intitle, string inauthor);
string getTitle();
void setTitle(string input);
string getAuthor();
void setAuthor(string input2);
};
#endif
Here is the .cpp file associated with the header file:
#include <iostream>
#include <math.h>
#include <string>
#include <string.h>
#include <fstream>
#include <stdio.h>
#include <cctype>
#include <locale>
#include <algorithm>
#include "Book.h"
using namespace std;
//Default constructor
Book::Book(){
author = "";
title = "";
}
//Parameterized Constructor
Book::Book(string intitle, string inauthor){
}
//An accessor function that returns the name of the title
string Book::getTitle() {
return title;
}
//A function that assigns the value title to the input given by the user
void Book::setTitle(string title){
title = intitle;
}
//An accessor function that returns the name of the author
string Book::getAuthor() {
return author;
}
//A function that assigns the value author to the input given by the user
void Book::setAuthor(string author){
author = inauthor;
}
And finally, here is the function I am trying to place it into (it is incomplete as every previous attempt I have made to use classes ends in a long list of errors and here is where I can confidently say I can get to):
#include <iostream>
#include <math.h>
#include <string>
#include <string.h>
#include <fstream>
#include <stdio.h>
#include <cctype>
#include <locale>
#include <algorithm>
#include "Book.h"
#include "User.h"
using namespace std;
int readBooks (string filename, int books[] , int bookObj, int capacity){
int i = 0;
ifstream file;
file.open (filename);
if (file.fail()){
return -1;
}
else{
string line;
while ((i < books) && (i < capacity) && (getline(file,line))){
}
}
I bet this is probably a very simple problem but neither the book or any other resources I have been referencing has been able to help me very much. Any help or advice would be greatly appreciated! Thank you!

Answer 1

I can help you out with your class design. It would look something like this:
Book.h
#ifndef BOOK_H
#define BOOK_H
#include <string>
#include <vector>
const int LIBRARY_MAX_CAPACITY = 200;
class Book {
private:
std::string author_;
std::string title_;
public:
Book() : author_( "" ), title_( "" ) {}
Book( const std::string& authorIn, const std::string& titleIn ) :
author_( authorIn ), title_( titleIn )
{}
void setAuthor( const std::string& authorIn ) {
this->author_ = authorIn;
// or just author_ = authorIn;
}
void setTitle( const std::string& titleIn ) {
this->title_ = titleIn;
// or just title_ = titleIn;
}
std::string getAuthor() const { return author_; }
std::string getTitle() const { return title_; }
};
void readBooks( const std::string& filename, std::vector<Book>& books );
#endif // BOOK_H
Book.cpp
#include "Book.h"
#include <fstream>
// this is just pseudo code and will not actually compile
void readBooks( const std::string& filename, std::vector<Book>& books ) {
// open file, test if open correctly
std::ifstream file;
file.open( filename );
// loop through file until end is reached by reading in
// a line of code and getting the contents of the book
while ( file still has data && line <= LIBRARY_MAX_CAPACITY ) {
// get a line of text then parse that line of text.
std::string author = "first string from file before comma"
std::string title = "second string from file after comma"
// create a book object here:
Book book( author, title );
// push back into vector that is passed into this function by reference
books.push_back( book );
}
// done with loop close the file
file.close();
}
Now what ever other function calls this function such as main, or your Library class etc. The std::vector<Book> object will be passed back by reference that is already populated with book objects and std::vector<> has a .size() function that returns it's size as an std::size_t.