Changing a .dat File

[toolnard]

Hello all,

I am working on an appointment planner, and I need to write a function to change an appointment. Each appointment has an ID. The user inputs the ID and what they want to change, and this then overwrites that area in the appointment. However, I can't get it to actually overwrite the old appointment. Everything seems to work except the edit_line function.

Here is the code so far:

#include <iostream>
#include <fstream>
#include <string>
#include <sstream>
#include <vector>
#include <cctype>
#include <strstream>
#include <iomanip>

using namespace std;

//initializing all functions and structures
int insert_newappointment(); string welcome_screen(); struct Date; struct Appointment; void show_all(); int check_id(int ID);



/*
==================
 Work
==================
*/

void edit_line()
{
	string id, appwith, day, month, year, starttime, duration, location;
	string test_id;
	cout << "Enter the appointment number to be edited: ";
	cin >> test_id;
	string change;
	cout << "Enter the attribute to be changed: (w for with, d for date, t for timing, l for location): ";
	cin >> change;
	fstream appointment_file;
	fstream new_file;
	new_file.open("test.dat");
	appointment_file.open("Appointments.dat");
	string line;
	cout << line << endl;
	while(getline(appointment_file, line))
	{

		istringstream isstream (line);
		ostringstream test (line);
 
		getline(isstream,id,';');
		if(test_id == id)
		{
			cout << "YAY!" << endl;
			getline(isstream,appwith,';');
			cout << appwith;
			appwith = "test";
			getline(isstream,day,';');
			getline(isstream,month,';');
			getline(isstream,year,';');
			getline(isstream,starttime,';');
			getline(isstream,duration,';');
			getline(isstream,location,';');
			test << id << appwith;
			string output = test.str();
			cout << output;
			new_file >> line;
		}
	}	
	system("pause");



}


/*
==================
End Work
==================
*/



//MAIN FUNCTION
int main()
{
	int quit;
	string line;

	do
	{
		string option_selected = welcome_screen();

		if(option_selected == "I" || option_selected == "i")
		{
			int keep_going=0;
			do
			{
				keep_going=insert_newappointment();
			}
			while(keep_going==1);
			quit=0;
		}
		else if (option_selected == "C" || option_selected == "c")
		{
			edit_line();
			quit=0;
		}
		else if (option_selected == "S" || option_selected == "s")
		{
			show_all();
			quit=0;
		}
		else if (option_selected == "Q" || option_selected == "q")
		{
			cout<<"Thank you for using the Appointments Planner!\n";
			quit=1;
		}
		else
		{
			cout<< "Option inputted not valid. Please try again.";
			quit=0;
		}
	}
	while(quit==0);

	system("pause");

	return 0;

}

//STRUCTURES AND FUNCTIONS

string welcome_screen()
{
		string choice;
		cout<< "************* Welcome to the Appointments Planner *************\n\n";
		cout<< "Please Select from one of the following options: \n";
		cout<< "\t I - to insert new appointment info\n";
		cout<< "\t C - to change the data for a particular existing appoint\n";
		cout<< "\t S - to show all the appointments\n";
		cout<< "\t Q - to quit this application\n";
		cout<< "Please enter one of the above letters: ";
		cin>> choice;
		cout<<endl;
		return choice;
}

struct Date
{
	string Day;
	string Month;
	string Year;
};

struct Appointment
{
	int appointmentID;
	string appointmentWith;
	Date appointmentDate;
	int appointmentStartTime;
	int appointmentDuration;
	string appointmentLocation;
};

int insert_newappointment()
{
	fstream appointment_file;
	appointment_file.open("Appointments.dat", ios::app);
	string line;
	int repeat=0;

	cout<< "Information regarding the new appointment: \n\n";

	Appointment file;
	Appointment* pointer;
	pointer=&file;

	do
	{
		cout<< "Enter the appointmentID: ";
		cin>>file.appointmentID;
		getline (cin, line);
		(stringstream) line>>pointer->appointmentID;
	}
	while(check_id(file.appointmentID)==1);


	cout<<"\nScheduled with: ";
	getline (cin, pointer->appointmentWith);

	cout<<"\nEnter the date of the appointment:";
	cout<<"\n    Day(DD): ";
	getline (cin, pointer->appointmentDate.Day);
	cout<<"\n    Month(MM): ";
	getline (cin, pointer->appointmentDate.Month);
	cout<<"\n    Year(YYYY):";
	getline (cin, pointer->appointmentDate.Year);

	cout<<"\nEnter the start time of appointment: ";
	getline (cin, line);
	(stringstream) line>>pointer->appointmentStartTime;

	cout<<"\nEnter the duration of appointment (in minutes): ";
	getline (cin, line);
	(stringstream) line>>pointer->appointmentDuration;

	cout<<"\nEnter the location of appointment: ";
	getline (cin, pointer->appointmentLocation);

	appointment_file<<endl<<pointer->appointmentID<< "; " <<pointer->appointmentWith<<"; "<<pointer->appointmentDate.Day<<"; "<<pointer->appointmentDate.Month<<"; "<<pointer->appointmentDate.Year<<"; "  << pointer->appointmentStartTime<< "; "<< pointer->appointmentDuration<< "; "<<pointer->appointmentLocation<< ";";

	appointment_file.close();

	cout<< "\nWould you like to enter another new appointment?\n";
	cout<< "Enter 1 for yes and 0 for no: ";
	cin>>repeat;
	//getline (cin, line);
	cout<<endl;

	return repeat;
};

void show_all()
{
	fstream appointment_file;
	appointment_file.open("Appointments.dat");

	string line;

	//		int appointmentID;
	//		string appointmentWith;

			string id, appwith, day, month, year, starttime, duration, location;
		
			cout << setw(8) << "ID" << setw(18) << "With" << setw(5) << "Day" << setw(6) << "Month" << setw(5) << "Year" << setw(6) << "Time" << setw(10) << "Duration" << setw(15) << "Location" << endl << endl;
			
			while (getline(appointment_file, line))
			{

				istringstream isstream (line);
 
				getline(isstream,id,';');
				getline(isstream,appwith,';');
				getline(isstream,day,';');
				getline(isstream,month,';');
				getline(isstream,year,';');
				getline(isstream,starttime,';');
				getline(isstream,duration,';');
				getline(isstream,location,';');

				cout << setw(8) << id << setw(18) << appwith << setw(5) << day << setw(6) << month << setw(5) << year << setw(6) << starttime << setw(10) << duration << setw(15) << location << endl;
			}
};

int check_id(int ID)
{
	fstream appointment_file;
	appointment_file.open("Appointments.dat");
	string line;
	int already_used=0;
	while(getline(appointment_file, line))
	{
		int appointmentID;
		appointment_file>>appointmentID;
		if (appointmentID==ID)
		{
			cout<< "\nAn appointment with that ID already exists. Please try again.\n\n";
			already_used=1;
			return already_used;
		}
	}
	return already_used;
};

Thank you for your help!

[hanst99]

Put code tags around your code so it becomes easier to read, and meanwhile check whether you actually close files you previously opened again.

[toolnard]

Sorry about that. Code tags have been added.

So if I close the files then the edit_line function will work?

[hanst99]

Depends on what you are trying to achieve with edit_line. It will do something, but I do question that it will do what you want it to.

[toolnard]

I'm certain it won't. My question is, how do I edit something in the "Appointments.dat" file? If I wanted to replace who the appointment was with, how do I do that?

Thank you.