Question

I’ve been working on this for a while now and I can’t seem to figure it out. I cannot compile the code as it keeps throwing the below error. Basically what Im trying to do is create a vector which contains objects from both a base and derived class using pointers.

Final Assignment.obj : error LNK2019: unresolved external symbol “public: __thiscall Product::Product(void)” (??0Product@@QAE@XZ) referenced in function “public: __thiscall SaleProduct::SaleProduct(char,class std::basic_string,class std::allocator >,int,double,double)” (??0SaleProduct@@QAE@DV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@HNN@Z)
fatal error LNK1120: 1 unresolved externals

#include "stdafx.h"
#include <iostream>
#include <fstream>
#include <iomanip>
#include <vector>
#include <string>
using namespace std;

class Product
{


public:

Product();
Product(char iT,string des,int inv,double p,double dis)
{
invType = iT;
description = des;
inventory = inv;
price = p;
discount = dis;
}

char getInvType(){
return invType;
}

protected:
char invType ;
string description;
int inventory;
double price;
double discount;
};

class SaleProduct:public Product {

public:



//SaleProduct();
SaleProduct(char iT,string des,int inv,double p,double dis){


}


};



int main()
{
int choice = 0;
// SaleProduct* SaleProductOB;
// Product *productPoint = &ProductOB;
 vector<Product*> inventoryVec;

  char invType;
  string description;
  int inventory;
  double price;
  double discount = 0;




ifstream inFile("Inventory.txt");

if (inFile.is_open()){

while (inFile >> invType >> description >> inventory >> price >>discount){

      if (invType == 'S'){

           inventoryVec.push_back(new SaleProduct(invType,description,inventory,price,discount)  );
     }else{
    //inventoryVec.push_back(new Product(invType,description,inventory,price,discount)  );

      }

}
}else{
cout << "File is not ready!";
}



cout << inventoryVec.size() << endl;


while (choice != 3) {
        cout << "Please enter your choice:" << endl;
        cout << "1. Print available items"  << endl;
        cout << "2. Add item to cart"       << endl;
        cout << "3. Print receipt and quit" << endl << endl;

        cin >> choice;
 }








//system("PAUSE");
return 0;
}

Answer 1

You may need to specify the correct constructor (as is, it is trying to use the default constructor, which has no actual definition):

SaleProduct(char iT,string des,int inv,double p,double dis) : 
   Product(iT, des, inv, p, dis ){