如何使我的构造函数和函数起作用，以便我的main（）能够同时显示字符串和int数据？

Question

I am learning about functions and classes, and wrote my own code. I used the constructor to just initialize the variables. I have a function that is supposed to get the info I initialized with the constructor and allow me to display it. However, it doesn't want to work. I am not really sure what I am doing wrong. My error code says that I have unresolved externals because of my "void" function. I thought my function was not returning anything but rather just displaying the input it got from the initialization of the constructor.

#include <iostream>
#include <iomanip>
#include <string>

using namespace std;

class Berries {

    string Nameofberries;
    int Price;

public:

    Berries (string N,int B)
    {
        Nameofberries = N;
        Price = B;
    }

    void GetBerryInfo(const Berries& B)
    {
        cout << B.Nameofberries << endl;
        cout <<  B.Price << endl;
    }
};

void GetBerryInfo (const Berries& B);

int main () 
{
    Berries Berryinfo1( "Raspberries", 7);
    cout << GetBerryInfo;
    system("pause");
    return 0;
}

Answer 1

There are several mistakes.

void GetBerryInfo(const Berries& B)
{
    cout <<  B.Nameofberries << endl;
    cout <<  B.Price << endl;
}

should be

void GetBerryInfo()
{
    cout <<  Nameofberries << endl;
    cout <<  Price << endl;
}

==================================================================

void GetBerryInfo (const Berries& B);

should be removed.

==================================================================

 cout << GetBerryInfo;

should be

 Berryinfo1.GetBerryInfo();

==================================================================

All computer langauges are fussy, you have to get the details right, as well as understand the concepts.

Answer 2

This will do what you wanted:

# include <iostream>
# include <iomanip>
# include <string>
using namespace std;

class Berries {

string Nameofberries;
int Price;

public:

Berries (string N,int B)
{
Nameofberries = N;
Price = B;
}
void GetBerryInfo()
{
    cout <<  Nameofberries << endl;
    cout <<  Price << endl;
}
};

int main () 
{
Berries Berryinfo1( "Raspberries", 7);
Berryinfo1.GetBerryInfo();

system("pause");
return 0;

}

A couple of points on your mistakes:

• GetBerryInfo() was declared inside the class. You don't need to re-declare it in the global scope. That 2nd declaration should be removed.
• To be invoked, functions (like GetBerryInfo ) must have () at the end of them like so: GetBerryInfo() .
• There is no point for GetBerryInfo() to take Berries as a paremeter. It is a member function that is part of the class Berries . It has access to all data members of a Berries instance already.
• You don't need to use cout here: cout << GetBerryInfo; because the function body already sends the data members to cout . This function returns void so it doesn't make sense to send this to cout anyway.