I am writing a program where a user enters from a menu and picks how they want to search from the file that is read. I know I made a few mistakes already but can someone point out and help me from them I will really appreciate it. This is what I have so far and completely lost with the user input I am getting a few errors.
#pragma once
#include <iostream>
#include <string>
#include <cstdlib>
#include <fstream>
#include <iomanip>
usingnamespace std;
class Book
{
private:
double amt; // book amount
string title; // book title
string author; // name of author
int year; // year of the book
public:
Book(); // constructor assigning the info to variables
double getamt(); // return amt
string gettitle(); // return title
string getauth(); // return author
int getyear(); // return year
};
books.txt
Author Title Year Price
-------------------------------------------------------------------------
1 2 3 4 5 6 7 8 9 10
Green Hunter Return of the light 2014 $19.50
Tom Freeman Hurting Beth 2012 $12.79
Billy Noris How It Hurts 2012 $12.79
Justin Jefferson Chandler Beths Story 2012 $12.79
Mitch Freeman Shooting for the Stars 2012 $12.79
Bob Freeman H.Q Secrets 2012 $12.79
Billy Noris Fun In The Middle 2012 $12.79
#include "library.h"
usingnamespace std;
int main()
{
cout << setw(4) << setprecision(4) << left << endl;
string line; // to read the files
int menu; // user choice to make when search for book
Book Info; // class object
ifstream infile; // opening the file
infile.open("books.txt"); // name of file
if (!infile.is_open()) // if file not read
{
cout << "an error occured please try again later" << endl;
}
else
{
cout << "here is the libary you wish to buy" << endl;
while (getline(infile, line))
{
cout << line << endl; // prints the text file to screen
}
}
// menu diagram
do
{
cout << "welcome to sample library what would you like to do \n\n --------" << endl;
cout << "enter 1) if you wish to search book titles " << endl;
cout << "enter 2) if you wish to search book price of the book " << endl;
cout << "enter 3) if you wish to search book author " << endl;
cout << "enter 4) if you wish to search book year " << endl;
cout << "enter 0) if you wish to exit the program " << endl;
cin >> menu;
} while (menu != 0);
// switch statment for the users input
switch (menu)
{
case 1:
cout << "\n please enter the title of the book" << endl;
cin >> Info.gettitle;
void titlesrch( /* send input to search book title*/);
break;
case 2:
cout << "\n please enter price of the book" << endl;
cin >> Info.getamt;
void pricesrch( /* send input to search book price*/);
break;
case 3:
cout << "\n please enter the author of the book" << endl;
cin >> Info.getauth;
void authrch( /* send input to search book author*/);
break;
case 4:
cout << "\n please enter year of the book" << endl;
cin >> Info.getyear;
void yearsrch( /* send input to search book year*/);
break;
case 5:
cout << "\n Thank you " << endl;
exit(0);
break;
}
system("pause");
return 0;
}
1. your class "Book" have no way of setting it's member values, maybe you should provide a constructor that takes arguments or some mutator functions e.g
1 2 3 4 5 6 7
Book(double,std::string,std::string,int)///in class declaration
Book::Book(double amount, std::string Title, std::string Author, int Yr)
:amt(amount), title(Title),author(Author),year(Yr)
{
}
2. you need a way to store your data once read from the txt, you could create a container of books and then you can access your items from there.
std::vector<Book> library_books;// populate your books here, you may need this for searching books by details rather than opening the file everytime.
3. you need a way of exiting your loop once you acquire user input.
consider this two function.
void PrintMenu()
{
std::cout << "welcome to sample library what would you like to do \n\n --------" << std::endl;
std::cout << "enter 1) if you wish to search book titles " << std::endl;
std::cout << "enter 2) if you wish to search book price of the book " << std::endl;
std::cout << "enter 3) if you wish to search book author " << std::endl;
std::cout << "enter 4) if you wish to search book year " << endl;
std::cout << "enter 0) if you wish to exit the program " << endl;
}
int GetUserInput()
{
PrintMenu();
int choice;
std::cin>>choice;
while( (choice <0 || choice >4) || !std::cin)
{
if(!std::cin)
{
std::cin.clear(); std::cin.ignore(1000,'\n');
}
PrintMenu();
std::cin>>choice;
}
return choice;
}
////usage
int userChoice = GetUserInput();
4. you seem to be declaring functions within your switch , you should instead define those functions elsewhere and the call them in your cases.
1 2 3 4 5
case 1:
cout << "\n please enter the title of the book" << endl;
cin >> Info.gettitle;
void titlesrch( /* send input to search book title*/);/// declare/define this function elsewhere
break;
Thank you andy1992 for the advise, I made a few changes from the program but i have a few questions
for the construtor on part one. When i made the changes i got an error saying no appropriate "default constructor available"
wasn't the constructor used to assign the private variables that way i can access them.
part 4, I don't think i got the input right for
cin >> Info.gettitle;
or would i have to use getline to get the whitespace?
sorry i am really new to this im a beginner.
