Default string value

Hi everyone,

I am wanting for my object to have a default string value when it is created. In this example, when I create a new Vehicle object, I would like the name variable to be set to "CAR" once it is created.

//Vehicle.h

#ifndef __VEHICLE_INCLUDED__
#define __VEHICLE_INCLUDED__

#include <iostream>
#include <string>

using namespace std;

class Vehicle
{
        int numWheels;
        int numDoors;
        std::string name;

        public:

        Vehicle(int wheels=4, int doors=4, string newName ="CAR");

        void setNumWheels(int wheels);
        void setNumDoors(int doors);
        void setName(const std::string &newName);


        int getNumWheels();
        int getNumDoors();
        std::string getName();
        void printNumWheels();
};

#endif

//Vehicle.cpp
#include <iostream>
#include "Vehicle.h"
#include <string>

using namespace std;


Vehicle::Vehicle(int wheels, int doors, string newName)
{
        numWheels = wheels;
        numDoors = doors;
        name = newName;
}

// Setters
void Vehicle::setNumWheels(int wheels) { numWheels = wheels; }
void Vehicle::setNumDoors( int doors)  { numDoors  = doors;  }

// Getters
int Vehicle::getNumWheels() { return numWheels; }
int Vehicle::getNumDoors()  { return numDoors ; }
string Vehicle::getName() { return name; }

void Vehicle::setName(const std::string &newName)
{
        name = newName;
}

//vehicle-test.cpp
#include <iostream>
#include "Vehicle.h"

using namespace std;

int main()
{
        // Creat an array of vehicles
        Vehicle garage[2];

        garage[0].setName("Jaguar\0");
        garage[1].setName("Audi");

        cout << garage[0].getName() << " has " << garage[0].getNumDoors() << " doors" << endl;
        cout << garage[1].getName() << endl;
        cout << garage[2].getName() << endl;

        return 0;
}

Program output:

1
2
3

Jaguar has 4 doors
Audi

I was expecting the last line of the program output to read "CAR", but it appears that the default value is not being done.

Many thanks

Disch (13742)

You are setting the default name correctly.

Your problem is something else:

        // Creat an array of vehicles
        Vehicle garage[2];  // <- you only have 2 vehicles in your garage
            // ie... [0] and [1] are valid indexes

        garage[0].setName("Jaguar\0");
        garage[1].setName("Audi");

        cout << garage[0].getName() << " has " << garage[0].getNumDoors() << " doors" << endl;
        cout << garage[1].getName() << endl;
        cout << garage[2].getName() << endl;  // <- OUT OF BOUNDS, this vehicle
            //  does not exist!

You are attempting to access a 3rd vehicle when you only have 2. Therefore you are stepping out of bounds of your array and accessing invalid memory.

Change your array to have 3 elements instead of 2.

MiiNiPaa (8886)

1
2
3

Vehicle garage[2]; //Create an array of 2 Vehicles, valid indices are [0] and [1]

cout << garage[2].getName() << endl; //Accessing out of bounds. Only luck have prevented crash here.

sugarat (14)

DOH!! Silly me.. I've been playing with the default value for so long I didn't even spot that. Thanks :-)

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