Need help adding convert method to existing Date class

[gator6688]

I have to enter a new method (convert() ) to a previous class. this method has to access the month, year and day and return a long integer such as year*10000 + month * 100 + day. I think I did it right but not sure. I will put what I wrote and welcome any comments. Thanks!

void convert(int, int, int);  // my method
 
void Date::convert(int, int, int)
{
    cout << "The date is "
         << setw(8) << year*10000+month*100+day;
}
 
 
firstDate.convert(4, 1, 2002);
    secondDate.convert(5, 1, 2007); // I don't think these are right.
 

I am a beginner so any help would be useful.

[weaknessforcats]

void convert(int, int, int); // my method

This is not part of any class. Where is your Date class??

void Date::convert(int, int, int)
{
cout << "The date is "
<< setw(8) << year*10000+month*100+day;
}

What are the arguments for?? You don't use them.

Also, this function doesn't convert anything. Instead it displays a string which is really part of your main().

The function should return the result of the conversion and the display of that result should be in main().

[gator6688]

Here is my class. I am new to this so I am going to make mistakes.

#include "stdafx.h"
#include <iostream>
#include <iomanip>
using namespace std;
 
class Date
{
    // data declaration section
private:
    int month;
    int day;
    int year;
 
    //methods declaration section
public:
    Date();
    Date(int, int, int);
    void setDate(int mm, int dd, int yyyy);
    void showDate();
    void convert(int, int, int);
};
 
// methods implementation section
Date::Date()
{
    month = 7;
    day = 4;
    year = 2005;
    cout << "From the default constructor:"
         << "\n Created a new Date object with data values"
         << "\n   month = " << month << " day = " << day
         << "  year = " << year << "\n\n";
}
 
Date::Date(int mm, int dd, int yyyy)
{
    month = mm;
    day = dd;
    year = yyyy;
    cout << "From the overloaded constructor:"
         << "\n Created a new Date object with data values"
         << "\n   month = " << month << " day = " << day
         << "   year = " << year << "\n\n";
}
 
void Date::setDate(int mm, int dd, int yyyy)
{
    month = mm;
    day = dd;
    year = yyyy;
}
 
void Date::showDate()
{
    cout << "The date is " << setfill('0')
         << setw(2) << month << '/'
         << setw(2) << day << '/'
         << setw(2) << year % 100;
}
 
void Date::convert(int, int, int)
{
    cout << "The date is "
         << setw(8) << year*10000+month*100+day;
}
 
int _tmain(int argc, _TCHAR* argv[])
{
    Date firstDate;
    Date secondDate(5,1,2006);
 
    firstDate.showDate();
    secondDate.showDate();
 
    secondDate.setDate(12,25,2007);
    secondDate.showDate();
 
    firstDate.convert(4, 1, 2002);
    secondDate.convert(5, 1, 2007);
    return 0;
}

[ilikepython]

Here is my class. I am new to this so I am going to make mistakes.

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

class Date
{
// data declaration section
private:
int month;
int day;
int year;

//methods declaration section
public:
Date();
Date(int, int, int);
void setDate(int mm, int dd, int yyyy);
void showDate();
void convert(int, int, int);
};

// methods implementation section
Date::Date()
{
month = 7;
day = 4;
year = 2005;
cout << "From the default constructor:"
<< "\n Created a new Date object with data values"
<< "\n month = " << month << " day = " << day
<< " year = " << year << "\n\n";
}

Date::Date(int mm, int dd, int yyyy)
{
month = mm;
day = dd;
year = yyyy;
cout << "From the overloaded constructor:"
<< "\n Created a new Date object with data values"
<< "\n month = " << month << " day = " << day
<< " year = " << year << "\n\n";
}

void Date::setDate(int mm, int dd, int yyyy)
{
month = mm;
day = dd;
year = yyyy;
}

void Date::showDate()
{
cout << "The date is " << setfill('0')
<< setw(2) << month << '/'
<< setw(2) << day << '/'
<< setw(2) << year % 100;
}

void Date::convert(int, int, int)
{
cout << "The date is "
<< setw(8) << year*10000+month*100+day;
}

int _tmain(int argc, _TCHAR* argv[])
{
Date firstDate;
Date secondDate(5,1,2006);

firstDate.showDate();
secondDate.showDate();

secondDate.setDate(12,25,2007);
secondDate.showDate();

firstDate.convert(4, 1, 2002);
secondDate.convert(5, 1, 2007);
return 0;
}[/code]

You should name your arguements:

void Date::convert(int year, int month, int day)
{
    cout << "The date is "
         << setw(8) << year*10000+month*100+day;
}
 

And also, like WFC said, your function should return a result:

long int Date::convert(int year, int month, int day)
{
    long int date = year * 10000 + month * 100 + day;
    return date;
}
 
main
    ...
    ...
    long int date = firstDate.convert(2000, 3, 23);
    cout << date << endl;
 

[RRick]

Your convert method doesn't know where it wants to get the data from. You specify parameters for convert, but you never use them. Instead convert uses with the values internal to Date (and set by the constructor or setDate).

What do you want convert to do? Should it use the values inside of Date or use what is passed to it? Your convert code does the first option. If this is the case, use setDate before you call convert. Since you're not using the parameters passed to convert, get rid of them. They are only confusing.

You still have the problem of what to do with the convert value. Currently, you are printing it out to cout. Do you need to return an integer value? If so, change convert to return an int and return the calculated value inside the method.

[gator6688]

Thanks for the help! I think I got it and understand it.

[weaknessforcats]

Should it use the values inside of Date or use what is passed to it? Your convert code does the first option.

I think you have this reversed. The code is:

long int Date::convert(int year, int month, int day)
{
long int date = year * 10000 + month * 100 + day;
return date;
}

This code is using the function arguiments. Local variables ar eused in preference to member variables.

The code should be:

long int Date::convert()
{
    long int date = this->year * 10000 + this->month * 100 + this->day;
    return date;
}