C++ Creating a 2 Parameter Constructor

Question

I've written a program to display a company's name and report name, however, I need to make it so that if someone does not enter anything the program displays two default names. I need to add a constructor with 2 parameters. I find that I'm confusing myself, and getting more and more lost. I've tried making my code look like that of the textbook example, but to no avail. Could someone please give me some pointers and a direction?

I am using C++ in Microsoft Visual Studios Express 2012, and here is my current code.

//This program displays a company's name and report. 
#include <iostream>
#include <string>
using namespace std;



class Heading
{   
private:
    string company;
    string report;

public:

    void storeInfo (string c, string r);

    string getCompany()
    {
        return company;
    }
    string getReport()
    {
        return report;
    }
};

void Heading::storeInfo(string c, string r)
{
company = c;
report = r;
}

void storeInfo(Heading&);
void showInfo(Heading);

int main()
{
Heading company;

storeInfo(company);
showInfo(company);

cin.ignore();
cin.get();

return 0;
}

/*****storeInfo*****/
void storeInfo(Heading &item)
{
string company;
string report;

cout << "\nPlease enter the company name.\n";
getline(cin, company);

cout << "\nPlease enter the report name.\n";
getline(cin,report);

item.storeInfo(company, report);
}

/*****showInfo*****/
void showInfo(Heading item)
{
cout << item.getCompany() << endl;
cout << item.getReport();
}

I don't see any constructors defined here. A constructor has the same name as the class, and no return type. — crashmstr
– crashmstr, Commented Oct 17, 2013 at 18:38
Would it be adding Heading(string company, string, report) to the public section of the class? — Moxy
– Moxy, Commented Oct 17, 2013 at 18:41
so I've added, Heading() { company = "ABC Industries"; report = "Report"; } Heading (string c, string r) { company = c; report = r; } But it won't display the default names if nothing is entered in the program, I must be missing something major. — Moxy
– Moxy, Commented Oct 17, 2013 at 19:53

Atle · Accepted Answer · 2013-10-17 19:07:34Z

4

Put this inside your class to create a constructor:

Heading() {
    company = "Default company";
    report = "Default report";
}

You can also do this:

Heading(const char *def_company, const char *def_report) {
     company = def_company;
     report = def_report;
}

And create new Heading-objects like this (dynamic memory):

Heading *object = new Heading("default company", "default report");

Or like this (allocated on the stack):

Heading object("default_company", "default report");

edited Oct 17, 2013 at 19:07

answered Oct 17, 2013 at 18:40

Atle

1,87712 silver badges10 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Qaz Over a year ago

I recommend using constructor initializer lists, not assigning to members inside the body. And I highly recommend not using that dynamic approach, but if you need it, use a smart pointer.

Luchian Grigore Over a year ago

How is your second initialization in static memory?

Vlad from Moscow · Accepted Answer · 2013-10-17 18:57:34Z

It is not clear what you actually want. Either you indeed do not know how to write a constructor or you need setters for the data members. If you need a constructor you could write

class Heading
{   
private:
    string company;
    string report;
    const char *default_company = "Unknown company";
    const char *default_report  = "Unknown report";

public:

    Heading( const std::string &company = default_company, const std::string &report = default_report )
        : company( company ), report( report )
    {
    }
    void storeInfo (string c, string r);

    string getCompany()
    {
        return company;
    }
    string getReport()
    {
        return report;
    }
};

If you need setters then simply name them appropriately. For example

void storeCompany( const std::string & );
void storeReport( const std::string & );

instead of storeInfo.

CouchDeveloper · Accepted Answer · 2013-10-17 19:04:42Z

0

One other approach is this in order to default initialize member variables:

class Heading
{
   ...

private:
    std::string company = "Default";
    std::string report = "Default";
};

For reference: Non-static data members Member initialization

edited Oct 17, 2013 at 19:04

answered Oct 17, 2013 at 18:55

CouchDeveloper

19.4k4 gold badges49 silver badges74 bronze badges

Collectives™ on Stack Overflow

C++ Creating a 2 Parameter Constructor

3 Answers 3

2 Comments

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

2 Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related