Assignments » File Handling - Binary File  »  set1

File Handling - Binary File

[Set – 2]

Question 1. Assuming the class EMPLOYEE given below, write functions in C++ to perform following:
(i) Write the objects of EMPLOYEE to a binary file.
(ii) Read the objects of EMPLOYEE from binary file and display them on screen.
class EMPLOYEE
{
            int ENO;
            char ENAME[10];
            public :
            void GETIT()
            {
                        cin >> ENO;
                        gets (ENAME);
            }
            void SHOWIT()
           {
                        cout <<ENO << ENAME <<endl;
            }
};

Question 2. Assuming the class Computer as follows :
class computer
{
            char chiptype[10];
            int speed;
            public:
                        void getdetails()
                        {
                                    gets(chiptype);
                                    cin>>speed;
                        }
                        void showdetails()
                        {
                                    cout << “Chip” << chiptype << “ Speed = “ << speed;
                        }
};
Write a function readfile( ) to read all the records present in an already existing binary file SHIP.DAT and display them on the screen, also count the number of records present in the file.

Question 3. Given a binary file STUDENT.DAT, containing records of the following class Student type
class Student
{
            char S_Admno[lO];    //Admission number of student
            char S_Name[30];       //Name of student
            int Percentage;            //Marks Percentage of student
            public:
                        void EnterData()
                        {
                                    gets(S_Admno);
                                    gets(S_Name);
                                    cin>>Percentage;
                        }
                        void DisplayData()
                        {
                                    cout << setw(12) << S_Admno;
                                    cout << setw(32) << S_Name;
                                   cout<<setw(3) << Percentage << endl;
                        }
                        int ReturnPercentage()
                        {return Percentage;}
};
Write a function in C++, that would read contents of file STUDENT.DAT and display the details of those Students whose Percentage is above 75.

Question 4. Observe the program segment given below carefully and fill the blanks marked as Statement 1 and Statement 2 using seekg() and tellg() functions for performing the required task.

#include <fstream.h>
class Employee
{
            int Eno;
            char Ename[20];
            public:
            //Function to count the total number of records
            int Countrec();
};

int Item::Countrec()
{
            fstream File;
            File.open("EMP.DAT", ios::binary | ios::in);
            __ ___ ____ ___ __ //Statement 1
            int Bytes =___ __ __ _ //Statement 2
            int Count = Bytes / sizeof(Item);
            File.close();
            return Count;
}

Question 5. Write a function in C++ to add new objects at the bottom of a binary file "STUDENT.DAT", assuming the binary file is containing the objects of the following class.
class STUD
{
            int Rno;
            char Name[20];
            public:
            void Enter()
            {cin >> Rno; gets(Name); }
            void Display()
            {cout << Rno << Name << endl;}
};

Question 6. Observe the program segment given below carefully and fill the blanks marked as Statement 1 and Statement 2 using seekp() and seekg() functions for performing the required task.
#include <fstream.h>
class Item
{
            int Ino;
            char Item[20];
            public:
            //Function to search and display the content from a particular record number
            void Search(int );
           //Function to modify the content of a particular record number
            void Modify(int);
 };

 void Item::Search(int RecNo)
{
            fstream File;
            File.open( “STOCK.DAT”, ios::binary | ios::in);
            ___ ___ ____ ___ //Statement 1
            File.read((char*)this, sizeof(Item));
            cout << Ino << ”==> ” << Item << endl;
            File.close();
}

void Item::Modify(int RecNo)
{
            fstream File;
            File.open( “STOCK.DAT”, ios::binary | ios::in | ios::out);
            cin>>Ino;
            cin.getline(Item, 20);
            ___ ____ ____ ____ //Statement 2
            File.write( (char*)this, sizeof(Item));
            File.close();
}