Program to write and read an object in, from binary file using write() and read() in C++
#include <iostream>
#include <fstream>
#define FILE_NAME "emp.dat"
using namespace std;
//class employee declaration
class Employee {
private :
int empID;
char empName[100] ;
char designation[100];
int ddj,mmj,yyj;
int ddb,mmb,yyb;
public :
//function to read employee details
void readEmployee(){
cout<<"EMPLOYEE DETAILS"<<endl;
cout<<"ENTER EMPLOYEE ID : " ;
cin>>empID;
cin.ignore(1);
cout<<"ENTER NAME OF THE EMPLOYEE : ";
cin.getline(empName,100);
cout<<"ENTER DESIGNATION : ";
cin.getline(designation,100);
cout<<"ENTER DATE OF JOIN:"<<endl;
cout<<"DATE : "; cin>>ddj;
cout<<"MONTH: "; cin>>mmj;
cout<<"YEAR : "; cin>>yyj;
cout<<"ENTER DATE OF BIRTH:"<<endl;
cout<<"DATE : "; cin>>ddb;
cout<<"MONTH: "; cin>>mmb;
cout<<"YEAR : "; cin>>yyb;
}
//function to write employee details
void displayEmployee(){
cout<<"EMPLOYEE ID: "<<empID<<endl
<<"EMPLOYEE NAME: "<<empName<<endl
<<"DESIGNATION: "<<designation<<endl
<<"DATE OF JOIN: "<<ddj<<"/"<<mmj<<"/"<<yyj<<endl
<<"DATE OF BIRTH: "<<ddb<<"/"<<mmb<<"/"<<yyb<<endl;
}
};
int main(){
//object of Employee class
Employee emp;
//read employee details
emp.readEmployee();
//write object into the file
fstream file;
file.open(FILE_NAME,ios::out|ios::binary);
if(!file){
cout<<"Error in creating file...\n";
return -1;
}
file.write((char*)&emp,sizeof(emp));
file.close();
cout<<"Date saved into file the file.\n";
//open file again
file.open(FILE_NAME,ios::in|ios::binary);
if(!file){
cout<<"Error in opening file...\n";
return -1;
}
if(file.read((char*)&emp,sizeof(emp))){
cout<<endl<<endl;
cout<<"Data extracted from file..\n";
//print the object
emp.displayEmployee();
}
else{
cout<<"Error in reading data from file...\n";
return -1;
}
file.close();
return 0;
}
Output
EMPLOYEE DETAILS
ENTER EMPLOYEE ID : 1001
ENTERNAME OF THE EMPLOYEE : Priya Kaushal
ENTER DESIGNATION : Student
ENTER DATE OF JOIN:
DATE : 21
MONTH: 11
YEAR : 2016
ENTER DATE OF BIRTH:
DATE : 15
MONTH: 09
YEAR : 1999
Date saved into file the file.
Data extracted from file..
EMPLOYEE ID: 1001
EMPLOYEE NAME: Priya Kaushal
DESIGNATION: Student
DATE OF JOIN: 21/11/2016
DATE OF BIRTH: 15/9/1999
Program to write and read an object in, from binary file using write() and read() in C++
Output