Thread: 4 digit year

I am trying to make this accept a 4 digit year. Here is the code I have so far.

Code:

using namespace std;	

DateClass::DateClass()
	: Month(0), Day(0), Year(0)
{
}
//--------------------------------------------------------------------------------
DateClass::DateClass(int MonthArg, int DayArg, int YearArg)
	: Month(MonthArg), Day(DayArg), Year(YearArg)
{
}
//--------------------------------------------------------------------------------
bool DateClass::Read(istream & InFile)
/*	Reads a date from InFile. Input is assumed to be in mm/dd/yy form.
	true returned if date not 0/0/0.
	Post: String read from InFile and parsed into Month, Day, and Year.
	true returned if date not 0/0/0. false returned otherwise.                    */
{
	lvpstring S, MonthStr, DayStr, YearStr;
	getline(InFile,S);

	MonthStr = S.substr(0,S.find('/'));
	S = S.substr(S.find('/')+1,S.length()-S.find('/')-1);
	DayStr = S.substr(0,S.find('/'));
	YearStr = S.substr(S.find('/')+1,S.length()-S.find('/')-1);

	Month = atoi(MonthStr.c_str());
	Day = atoi(DayStr.c_str());
	Year = atoi(YearStr.c_str());

	return ((Month!=0) && (Day!=0) && (Year!=0));
}
//--------------------------------------------------------------------------------
void DateClass::SetDate(int MonthArg, int DayArg, int YearArg)
{
	Month = MonthArg;
	Day = DayArg;
	Year = YearArg;
}
//--------------------------------------------------------------------------------
void DateClass::Write(ostream & OutFile) const
/*	Writes D to the output stream
	Post: D written to OutFile                */
{
	OutFile.width(2); OutFile << Month << '/';
	OutFile.width(2); OutFile << Day << '/';
	OutFile.width(2); OutFile << Year;
}
//--------------------------------------------------------------------------------
bool DateClass::operator <(const DateClass Date2) const
{
	if (Year < Date2.Year)
		return (true);
	else if (Year > Date2.Year)
		return (false);
	else if (Month < Date2.Month)
		return (true);
	else if (Month > Date2.Month)
		return (false);
	else
		return (Day < Date2.Day);
}
//--------------------------------------------------------------------------------
bool DateClass::operator > (const DateClass Date2) const
{
	return (!(operator==(Date2)) && !(operator<(Date2)));
}
//--------------------------------------------------------------------------------
bool DateClass::operator == (const DateClass Date2) const
{
	return ((Day == Date2.Day) && (Month == Date2.Month) &&
		(Year == Date2.Year));
}
//--------------------------------------------------------------------------------
bool DateClass::operator != (const DateClass Date2) const
{
	return !(operator==(Date2));
}
//--------------------------------------------------------------------------------
bool DateClass::operator >= (const DateClass Date2) const
{
	return ((operator==(Date2)) || (operator>(Date2)));
}
//--------------------------------------------------------------------------------
bool DateClass::operator <= (const DateClass Date2) const
{
	return ((operator==(Date2)) || (operator<(Date2)));
}


//--------------------------------------------------------------------------------
ostream& operator << (ostream & OutFile, const DateClass &D)
{
	D.Write(OutFile);
	return (OutFile);
}
//--------------------------------------------------------------------------------
istream & operator >>(istream &InFile, DateClass &D)
/*	Reads from InFile to D
	Post: D is read from Infile */
{
	D.Read(InFile);
	return (InFile);
}

Here is my date.h file

Code:

#ifndef _DATECLASS_
#define _DATECLASS_

#include <iostream.h>
#include <lvpstring.h>

#include <stdlib.h>  // for atoi()

using namespace std;	

class DateClass {
public:
	DateClass();
	DateClass(int MonthArg, int DayArg, int YearArg);

	bool Read(istream & InFile);
	void SetDate(int MonthArg, int DayArg, int YearArg);
	void Write(ostream & OutFile) const;

	bool operator ==(const DateClass Date2) const;
	bool operator !=(const DateClass Date2) const;
	bool operator <(const DateClass Date2) const;
	bool operator <=(const DateClass Date2) const;
	bool operator >(const DateClass Date2) const;
	bool operator >=(const DateClass Date2) const;

private:
	int Month;
	int Day;
	int Year;
};

#include "date.cpp"
#endif

what is the problem youre having?

It takes a two digit year. I am trying to get it to use a four digit year so it knows 12/10/03 is 2003 and not 1903

If you want two digit years such as 03 to evaluate correctly, you need to take the current century into account as well.

How would I go about doing that?

I have been playing arounf with this and I think I need to make a change somewhere in this piece of code.

Code:

bool DateClass::Read(istream & InFile)
/*	Reads a date from InFile. Input is assumed to be in mm/dd/yy form.
	true returned if date not 0/0/0.
	Post: String read from InFile and parsed into Month, Day, and Year.
	true returned if date not 0/0/0. false returned otherwise.                    */
{
	lvpstring S, MonthStr, DayStr, YearStr;
	getline(InFile,S);

	MonthStr = S.substr(0,S.find('/'));
	S = S.substr(S.find('/')+1,S.length()-S.find('/')-1);
	DayStr = S.substr(0,S.find('/'));
	YearStr = S.substr(S.find('/')+1,S.length()-S.find('/')-1);

	Month = atoi(MonthStr.c_str());
	Day = atoi(DayStr.c_str());
	Year = atoi(YearStr.c_str());

	return ((Month!=0) && (Day!=0) && (Year!=0));
}

I want it to be mm/dd/yyyy and not mm/dd/yy