Program 9

BINARY FILE HANDLING - III

Define  a class Mobile with the following members:

          Private members:

                   Mob_id                            -        char array

                   Mob_name                      -        char array

                    Price                                -        float

          Public members:

                   void getMob ( )                -        to accept Mobile details

                   void putMob ( )               -        to display Mobile details

                   void addBook ( )              -        to add Book records to a file

                   int CheckMob(char [ ] )  -        to check if mod_id is matching

                   void disBook( )                -        to display contents of the file

    Write a user defined functions to

i)             Append Mobile records to a file

ii)           Update a Mobile record after accepting the mob_id from user

iii)          Display the Mobile records

#include<conio.h>

#include<string.h>

#include<stdio.h>

#include<fstream.h>

#include<process.h>

class Mobile

 {

          char mob_id [ 20 ] , mob_name [ 30 ];

          float price ;

    public  :

          void getMob ( )

            {

                   cout << "\nEnter Mobile ID , Mobile Name and Price:" ;

                   gets ( mob_id ) ;

                   gets ( mob_name ) ;

                   cin >> price ;

            }

          void putMob ( )

            {

                   cout << "\nMobile ID , Mobile Name and Price:" ;

                   puts ( mob_id ) ;

                   puts ( mob_name ) ;

                   cout << price ;

            }

          int checkMob ( char mid [ ] )     // fun returns 0 or 1

            {

                   return   strcmpi  (  mob_id ,  mid ) ;

            }

 } M ;

void append ( )

 {

  ofstream   fout ( "mobile . dat" , ios  ::  app | ios  ::  binary ) ;

  if ( ! fout )

   {

          cout << "\nError Opening File" ;

          getch ( ) ;

          exit ( 0 ) ;

   }

  M . getMob ( ) ;

  fout . write ( ( char * ) & M  , sizeof ( M ) ) ;

  fout . close ( ) ;

  cout << "\nMobile Details added" ;

 }

void update ( )

 {

  ifstream fin ( "mobile . dat" ,  ios  ::  binary ) ;

  if ( ! fin )

   {

    cout << "\nError Opening File" ;

    getch ( ) ;

    exit ( 0 ) ;

   }

  int f = 0 , pos = -1 ;

  char mid [ 20 ] ;

  cout << "\nEnter the ID of the mobile to be updated" ;

  gets ( mid ) ;

  while ( fin . read ( ( char *) & M , sizeof ( M ) ) )

   {

    if  ( M . checkMob ( mid ) == 0 )

     {

               f =1 ;

               pos =  fin . tellg ( ) ;

               pos = pos – sizeof ( Mobile ) ;

               break ;

     }

   }

   fin.close ( ) ;

   if ( f == 0 )

     cout << "\nMobile Id Not Found!!"  ;

   else

     { 

             M . getMob( ) ;

             ofstream fout ( "Mobile . dat" ,  ios :: binary | ios :: ate  ) ;

             fout . seekp ( pos ) ;

             fout . write ( ( char * ) & M , sizeof ( M) ) ;

             fout . close ( ) ;

             cout << “ Updated !!”;

       }

  }

void disp ( )

 {

           ifstream  fin ( "mobile . dat ",  ios  ::  binary) ;

          while( fin . read ( ( char * ) & M , sizeof ( M ) ) )

                   M . putMob ( ) ;

          fin . close ( ) ;

          getch ( ) ;

   }

    

 }

void main ( )

 {

  int ch ;

  while ( 1 )

  {

            clrscr ( ) ;

            cout << "\n         MENU\n     @*@*" ;

            cout << "\n\n\n1.       Append Mobile Records" ;

            cout << "\n2.      Update Mobile Records" ;

            cout<< ”\n3.       Display Mobile Records” ;

            cout << "\n4.      Exit " ;

            cout << "\n\n Enter choice" ;

            cin >> ch ;

            if ( ch == 1 )                  append ( ) ;

            else if ( ch == 2 )       update( ) ;

            else if ( ch == 3 )       disp ( ) ;

            else if ( ch == 4 )

             {

                   cout << "Exiting....." ;

                   getch ( ) ;

                   exit ( 0 ) ;

             }

            else 

cout << "\nInvalid Choice" ;

            getch ( ) ;

  }

 }