Mega Code Archive
Creating a randomly accessed file
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#include <iostream>
using std::cerr;
using std::endl;
using std::ios;
#include <fstream>
using std::ofstream;
#include <cstdlib>
using std::exit;
#include <string>
using std::string;
class Account
{
public:
Account( int accountNumberValue, string lastNameValue, string firstNameValue, double balanceValue )
{
setAccountNumber( accountNumberValue );
setLastName( lastNameValue );
setFirstName( firstNameValue );
setBalance( balanceValue );
}
int getAccountNumber() const
{
return accountNumber;
}
void setAccountNumber( int accountNumberValue )
{
accountNumber = accountNumberValue; // should validate
}
string getLastName() const
{
return lastName;
}
void setLastName( string lastNameString )
{
const char *lastNameValue = lastNameString.data();
strncpy( lastName, lastNameValue, 5 );
lastName[ 5 ] = '\0';
}
string getFirstName() const
{
return firstName;
}
void setFirstName( string firstNameString )
{
const char *firstNameValue = firstNameString.data();
strncpy( firstName, firstNameValue, 5 );
firstName[ 5 ] = '\0';
}
double getBalance() const
{
return balance;
}
void setBalance( double balanceValue )
{
balance = balanceValue;
}
private:
int accountNumber;
char lastName[ 15 ];
char firstName[ 10 ];
double balance;
};
int main()
{
ofstream outCredit( "credit.dat", ios::binary );
if ( !outCredit )
{
cerr << "File could not be opened." << endl;
exit( 1 );
}
Account blankClient(1,"AAAAA","BBBBB",1.2);
// output 100 blank records to file
for ( int i = 0; i < 100; i++ )
outCredit.write( reinterpret_cast< const char * >( &blankClient ),
sizeof( Account ) );
return 0;
}
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