Question

Write in C++

1. Use the following Person class (Person.cpp, Person.h). You will be writing Person objects to a random access file.

--------------------- Person.cpp---------------------------------
// Class Person stores customer's credit information.
#include <string>
#include "Person.h"
using namespace std;

// default Person constructor
Person::Person( int idValue, 
   string lastNameValue, string firstNameValue, int AgeValue )
{
   setID( idValue );
   setLastName( lastNameValue );
   setFirstName( firstNameValue );
   setAge( AgeValue );
} // end Person constructor

// get id value
int Person::getID() const
{
   return id;
} // end function geID

// set id value
void Person::setID( int idValue )
{
   id = idValue; // should validate
} // end function setID

// get last-name value
string Person::getLastName() const
{
   return lastName;
} // end function getLastName

// set last-name value
void Person::setLastName( string lastNameString )
{
   // copy at most 14 characters from string to lastName
   int length = lastNameString.size();
   length = ( length < 15 ? length : 14 );
   lastNameString._Copy_s(lastName, 15, length); 
   lastName[ length ] = '\0'; // append null character to lastName
} // end function setLastName

// get first-name value
string Person::getFirstName() const
{
   return firstName;
} // end function getFirstName

// set first-name value
void Person::setFirstName( string firstNameString )
{
   // copy at most 14 characters from string to firstName
   int length = firstNameString.size();
   length = ( length < 15 ? length : 14 );  
   firstNameString._Copy_s(firstName, 15, length);
   firstName[ length ] = '\0'; // append null character to firstName
} // end function setFirstName

// get age value
int Person::getAge() const
{
   return age;
} // end function getAge

// set age value
void Person::setAge( int ageValue )
{
   age = ageValue;
} // end function setAge

--------------------- Person.h ---------------------------------

// Class Person definition
#ifndef PERSON_H
#define PERSON_H

#include <string>
using namespace std;

class Person 
{
public:
   // default Person constructor
   Person( int = 0, string = "unassigned", string = "unassigned", int = 0 );

   // accessor functions for id
   void setID( int );
   int getID() const;

   // accessor functions for lastName
   void setLastName( string );
   string getLastName() const;

   // accessor functions for firstName
   void setFirstName( string );
   string getFirstName() const;

   // accessor functions for age
   void setAge( int );
   int getAge() const;
private:
   int id;
   char lastName[ 15 ];
   char firstName[ 15 ];
   int age;
}; // end class Person

#endif

2. Create and initialize a random access file named nameage.dat with 50 records that store the values of 0 for the id, unassigned for the first and last name and 0 for the age. This code only needs to be executed once. Once you have written the code to create and initialize this file comment out this code (do not delete the code because you are being graded on this code also).

3.The user of your program should see a menu allowing them to write a Person object to the file, update an existing Person object's age, delete a Person object, display a particular Person object from the file, or exit the program.

a.	The first four options of the menu should ask the user for a record number (id) which will identify where in the random access file to write, update, delete, or display the Person object. Write the code to make sure the value the user inputs is from 1 to 50 only (an id of 1 should write to position 0 in the file).
b.	Make sure the user does not overwrite an existing record when writing a new Person object to the file.
c.	If the user wants to update an existing Person's age, make sure a valid Person object exists in the file for the id the user enters before asking for and updating the age. A valid Person object would be a Person object that does not have, for example, a 0 for the id or unassigned for the first and last name.
d.	Deleting a Person object from the file involves writing a blank Person object to the file (id set to 0, first and last name set to unassigned, and age set to 0).
e.	If the user wants to display a Person object, make sure a valid Person object exists in the file for the id the user enters before displaying the Person object.

4. Sample output.

******* MENU *******
1 - Write a new person
2 - Update the age of an existing person
3 - Delete a person
4 - Display a person
5 - Exit

Enter an integer for what you want to do: 1
Please enter a record number (1-50): 23
Enter the persons first name : Jane
Enter the persons last name : Doe
Enter the persons age : 25

New person added
ID First name Last name Age
23 Jane Doe 25

******* MENU *******
1 - Write a new person
2 - Update the age of an existing person
3 - Delete a person
4 - Display a person
5 - Exit

Enter an integer for what you want to do: 1
Please enter a record number (1-50): 23
A person already exists with that number returning to the menu.

******* MENU *******
1 - Write a new person
2 - Update the age of an existing person
3 - Delete a person
4 - Display a person
5 - Exit

Enter an integer for what you want to do: 4
Please enter a record number (1-50): 44
There is no person with that id.

******* MENU *******
1 - Write a new person
2 - Update the age of an existing person
3 - Delete a person
4 - Display a person
5 - Exit

Enter an integer for what you want to do: 4
Please enter a record number (1-50): 23
ID First name Last name Age
23 Jane Doe 25

******* MENU *******
1 - Write a new person
2 - Update the age of an existing person
3 - Delete a person
4 - Display a person
5 - Exit

Enter an integer for what you want to do:

Answer 1

Hello,

Here is the complete code. Let me know if any modification are required.

Person.h

// Class Person definition
#ifndef PERSON_H
#define PERSON_H

#include <string>
#include <fstream>
#include<iostream>
using namespace std;

class Person
{
public:
   // default Person constructor
   Person(int = 0, string = "unassigned", string = "unassigned", int = 0);

   // accessor functions for id
   void setID(int);
   int getID() const;

   // accessor functions for lastName
   void setLastName(string);
   string getLastName() const;

   // accessor functions for firstName
   void setFirstName(string);
   string getFirstName() const;

   // accessor functions for age
   void setAge(int);
   int getAge() const;

   // Static functions to update file and read from file
   static void updateFile(Person *person[], int size);
   static void readFile(Person *person[]);

   static const string fileName;   // Name of file

private:
   int id;
   char lastName[15];
   char firstName[15];
   int age;
}; // end class Person

#endif

Person.cpp

#include "Person.h"

// default Person constructor
Person::Person(int idValue,   string lastNameValue, string firstNameValue, int AgeValue)
{
   setID(idValue);
   setLastName(lastNameValue);
   setFirstName(firstNameValue);
   setAge(AgeValue);
} // end Person constructor

// get id value
int Person::getID() const
{
   return id;
} // end function geID

// set id value
void Person::setID(int idValue)
{
   id = idValue; // should validate
} // end function setID

// get last-name value
string Person::getLastName() const
{
   return lastName;
} // end function getLastName

// set last-name value
void Person::setLastName(string lastNameString)
{
   // copy at most 14 characters from string to lastName
   int length = lastNameString.size();
   length = (length < 15 ? length : 14);
   lastNameString._Copy_s(lastName, 15, length);
   lastName[length] = '\0'; // append null character to lastName
} // end function setLastName

// get first-name value
string Person::getFirstName() const
{
   return firstName;
} // end function getFirstName

// set first-name value
void Person::setFirstName(string firstNameString)
{
   // copy at most 14 characters from string to firstName
   int length = firstNameString.size();
   length = (length < 15 ? length : 14);
   firstNameString._Copy_s(firstName, 15, length);
   firstName[length] = '\0'; // append null character to firstName
} // end function setFirstName

// get age value
int Person::getAge() const
{
   return age;
} // end function getAge

// set age value
void Person::setAge(int ageValue)
{
   age = ageValue;
} // end function setAge

// Initialize the file name
const string Person::fileName = "nameage.dat";

// Update details into file
void Person::updateFile(Person *person[], int size)
{
   fstream file;

   // Open the file in write mode
   file.open(fileName, fstream::out);
   if (file.fail())
   {
       cout << "File cannot be opened for writing";
       return;
   }

   // Write the details into file
   for (int i = 0; i < size; i++)
       file << person[i]->getID() << " " << person[i]->getFirstName() << " " << person[i]->getLastName() << " " << person[i]->getAge() << "\n";

   file.close();
}

// Read the file to get the person details
void Person::readFile(Person *person[])
{
   fstream file;
   int id, age, i = 0;
   string fname, lname;

   // Open the file in read mode
   file.open(fileName, fstream::in);
   if (file.fail())
   {
       cout << "File cannot be opened for writing";
       return;
   }

   // Read till the file reaches end of file
   while (!file.eof())
   {
       // Read data from file
       file >> id >> fname >> lname >> age;

       // Create new instance of Person with the read data
       person[i++] = new Person(id, fname, lname, age);
   }

   file.close();
}

main.cpp

#include "Person.h"

// Number of entries in nameage.dat file
#define SIZE 50

void main()
{
   Person *person[SIZE];
   int option, i = 0;
   bool stop = false, found;

   int id, age;
   string fname, lname;

   /* Uncomment this code to initialize random access file with initial values for the first execute*/
   // Create new instance for given size
   /*for (int i = 0; i < SIZE; i++)
       person[i] = new Person();

   // Update the file with initial values
   Person::updateFile(person, SIZE);*/

   // Read details from acess file
   Person::readFile(person);

   // Get into infinate loop where only user is allowed to exit
   while (!stop)
   {
       found = false;
       system("cls");

       // Display the initial screen and options
       cout << "******* MENU *******" << endl;
       cout << "1 - Write a new person" << endl;
       cout << "2 - Update the age of an existing person" << endl;
       cout << "3 - Delete a person" << endl;
       cout << "4 - Display a person" << endl;
       cout << "5 - Exit" << endl;

       cout << "Enter an integer for what you want to do: ";
       cin >> option;
       fflush(stdin);

       // Action for the selection option
       switch (option)
       {
       case 1:       // Write a new person
           // Get person id
           cout << "Please enter a record number (1-50): ";
           cin >> id;
           fflush(stdin);

           // Check whether person is not already created for the given ID
           if (person[id - 1]->getID() != 0)
               found = true;

           // Create new person for if not found
           if (!found)
           {
               // Get further details of person
               cout << "Enter the persons first name : ";
               getline(cin, fname);
               cout << "Enter the persons last name : ";
               getline(cin, lname);
               cout << "Enter the persons age : ";
               cin >> age;

               person[id - 1]->setID(id);
               person[id - 1]->setFirstName(fname);
               person[id - 1]->setLastName(lname);
               person[id - 1]->setAge(age);
              
               // Update the file
               Person::updateFile(person, SIZE);

               // Display the confirmation
               cout << "ID\tFirst name\tLast name\tAge" << endl;
               cout << id << "\t" << fname << "\t\t" << lname << "\t\t" << age << endl;
           }
           else
           {
               // Person is already exists
               cout << "A person already exists with that number returning to the menu." << endl;
           }

           break;
          
       case 2:       // Update the age of an existing person
           // Get person id
           cout << "Please enter a record number (1-50): ";
           cin >> id;
           fflush(stdin);

           // Check whether given person ID already exists
           if (person[id - 1]->getID() == id)
               found = true;

           // Update the record if person already exists
           if (found)
           {
               // Get age of person to update
               cout << "Enter the persons age : ";
               cin >> age;

               // Update age
               person[id - 1]->setAge(age);

               // Update the file
               Person::updateFile(person, SIZE);

               // Display the confirmation
               cout << "ID\tFirst name\tLast name\tAge" << endl;
               cout << id << "\t" << fname << "\t\t" << lname << "\t\t" << age << endl;
           }
           else
           {
               // Person is not created for given ID
               cout << "A person with that number doesn't exists." << endl;
           }

           break;

       case 3:       // Delete a person
           // Get person ID
           cout << "Please enter a record number (1-50): ";
           cin >> id;
           fflush(stdin);

           // Check whether given person ID already exists
           if (person[id - 1]->getID() == id)
               found = true;
          
           // Delete the person if id found
           if (found)
           {
               // Initialize the current person
               person[id - 1] = new Person();

               // Update the file
               Person::updateFile(person, SIZE);

               cout << "A person with that number removed successfully." << endl;
           }
           else
           {
               // Person doesn't exists for given ID
               cout << "A person with that number doesn't exists." << endl;
           }

           break;

       case 4:       // Display a person
           // Get person id
           cout << "Please enter a record number (1-50): ";
           cin >> id;
           fflush(stdin);

           // Display the matching person ID
           if (person[id - 1]->getID() == id)
           {
               fname = person[id - 1]->getFirstName();
               lname = person[id - 1]->getLastName();
               age = person[id - 1]->getAge();
               cout << "ID\tFirst name\tLast name\tAge" << endl;
               cout << id << "\t" << fname << "\t\t" << lname << "\t\t" << age << endl;
           }
           else
           {
               cout << "A person with that number doesn't exists." << endl;
           }

           break;
          
       case 5:       // Exit
           stop = true;
           break;
       }

       system("pause");
   }
}

Output