Create objects in conditional c++ statements

I am learning c++, and I just got to the object oriented chapter. I have a question about creating objects inside if statements.

The problem I'm working on says to create a class that will display a report header. The class has a default constructor that sets the company name and report name to a generic thing, and also, if the user wants, has a constructor that takes two arguments (strings company name and report name).

The problem says, specifically, "A two-parameter default constructor should allow these [company and report names] to be specified at the time a new Report object is created. If the user creates a Report object without passing any arguments, use the default values. Otherwise, use user specified values for the names."

So my question is, how to create these objects? I understand how to create an object without any arguments (i.e. Report newobj;), and also with arguments (i.e. Report newobj(string string);). Basically, I get how to create these objects initially at the top of my main function. But is it possible to create them inside if statements based on user choices? Here is what I have so far and, obviously, it doesn't work:

#include <iostream>
#include <string>
#include "report.h"
using namespace std;

bool enter_company_name();           // return true if user wants to enter company name
bool print_form();              // return true if user wants to print in formatted output

int main()
{
  string company_name,
    report_name;
  bool name = false,
    format = false;

  name = enter_company_name();
  format = print_form();

  if (name)
    {
      cout << "Enter company name: ";
      getline(cin, company_name);
      cout << "Enter report name: ";
      getline(cin, report_name);
      Report header(company_name, report_name);  // THIS IS MY PROBLEM
    }
  else
      Report header;  // THIS IS MY PROBLEM

  if (format)
    header.print_formatted();
  else
    heade


                    
                    
                        
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I'm not sure if I understood your question properly. Apologies if you read the answer and realise that that's the case.

But nevertheless, I think the main strategy would be to make use of constructor overloading. ie, you define constructors for both: the case when no parameters are passed and the case when parameters are passed. The former(what you refer to as default constructor) will initialise the company and report names to default values. The latter will assign the parameters received, to the comapany and report names.

As for the use of pointers: you can avoid it by 'declaring' a lot of objects of type 'Report'(class). For eg, you can create an array of header(objects). And then you can 'define' it as and when the user responds.

But by using pointers, you're doing everything in runtime(dynamic assignment) whereas when using arrays(or declaring many objects): the amount is fixed. This can be inefficient.

answered 2012-02-19T04:01:06.023

Create objects in conditional c++ statements

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