When i execute the program and select option number 2 it reads the data from the file successfully but when i select the option number 2 for the second time , third time and so on... nothing comes up and it returns back to the menu. I have tried so many times, same error comes every time. PLEASE HELP. Thanks to all in advance. love all.
#include <fstream>
#include <cstdlib>
#include <cstdio>
#include <string>
#include <iomanip>
#include <iostream>
using namespace std;
//class for database functions
class group
{
private:
struct person {
char flag;
char empcode[5];
char name[10];
int age;
float sal;
}p;
public:
fstream file,t_file;
ifstream fin;
ofstream fout;
group();
void addrec();
void listrec();
void modirec();
void delrec();
void recovrec();
};
//main function
int main()
{
char choice;
group g;
do
{
system("cls");
cout<<"1.Add Records"<<endl;
cout<<"2.List Records"<<endl;
cout<<"3.Modify Records"<<endl;
cout<<"4.Delete A Record"<<endl;
cout<<"5.Recover Deleted Records"<<endl;
cout<<"6.Exit"<<endl;
cout<<"Your choice ?: ";
cin>>choice;
system("cls");
switch(choice)
{
case '1':
g.addrec();
break;
case '2':
g.listrec();
break;
case '3':
g.modirec();
break;
case '4':
g.delrec();
break;
case '5':
g.recovrec();
break;
case '6':
exit(0);
}
} while(choice!=6);
return 0;
}
//default constructor
group::group()
{
file.open("EMP.DAT",ios::in|ios::out|ios::binary);
p.flag=' ';
if(!file)
cerr<<"Unable to open file";
}
//Add records at the end
void group::addrec()
{
char ch;
cout<<"Do You Want To Erase Previous Records ?: ";
cin>>ch;
if(ch=='y'||ch=='Y')
remove("EMP.DAT");
fout.open("EMP.DAT",ios::binary);
fout.seekp(0L,ios::end);
system("cls");
do
{
cout<<"Enter Emp_Code, Name, age, Salary"<<endl;
cin>>p.empcode>>p.name>>p.age>>p.sal;
fout.write((char*)&p,sizeof(p));
cout<<"Add another record ?: ";
cin>>ch;
} while(ch=='y'||ch=='Y');
fout.close();
}
//list all the records
void group::listrec()
{
int j=0;
//position get pointer at beginning
//fin.open("EMP.DAT",ios::binary);
file.seekg(0L,ios::beg);
while(file.read((char*)&p,sizeof(p)))
{
if(p.flag!='*')
{
cout<<"\nRecord N. "<<++j;
cout<<"\nEmp Code: "<<p.empcode;
cout<<"\nName: "<<p.name;
cout<<"\nAge: "<<p.age;
cout<<"\nSalary: "<<p.sal<<endl;
}
}
cin.ignore();
getchar();
}
//modifies a given record from file
void group::modirec()
{
char code[5];
int count=0;
long int pos;
cout<<"Enter Emp Code";
cin>>code;
file.open("EMP.DAT",ios::in|ios::out|ios::binary);
file.seekg(0,ios::beg);
//search an employee
while(file.read((char*)&p,sizeof(p)))
{
//if record is found
if(strcmp(p.empcode,code)==0&&p.flag==' ')
{
//recieve new data
cout<<"Enter new Data: "<<endl;
cout<<"Enter Emp_Code, Name, age, Salary"<<endl;
cin>>p.empcode>>p.name>>p.age>>p.sal;
//position put pointer to overwrite record
pos=count*sizeof(p);
file.seekp(pos,ios::beg);
file.write((char*)&p,sizeof(p));
file.close();
cout<<endl<<"Press Any Key...";
getchar();
return;
}
count++;
}
file.close();
cout<<endl<<"No Employee In File With Code: "<<code;
cout<<endl<<"Press Any Key...";
getchar();
}
//marks a record for deletion
void group::delrec()
{
char code[5];
long int pos;
int count =0;
cout<<"Enter Emp Code";
cin>>code;
file.open("EMP.DAT",ios::in|ios::out|ios::binary);
//position pointer at beginning
file.seekg(0L,ios::beg);
//search an employee
while(file.read((char*)&p,sizeof(p)))
{
//if record is found
if(strcmp(p.empcode,code)==0&&p.flag==' ')
{
p.flag='*';
//position put pointer
pos=count*sizeof(p);
file.seekp(pos,ios::beg);
file.write((char*)&p,sizeof(p));
file.close();
return ;
}
count++;
}
cout<<endl<<"No Employee In File With Code: "<<code;
file.close();
cout<<endl<<"Press Any Key...";
getchar();
}
//unmarkmarks a record
void group::recovrec()
{
char code[5];
long int pos;
int count =0;
cout<<"Enter Emp Code";
cin>>code;
file.open("EMP.DAT",ios::in|ios::out|ios::binary);
//position pointer at beginning
file.seekg(0L,ios::beg);
//search an employee
while(file.read((char*)&p,sizeof(p)))
{
//if record is found
if(strcmp(p.empcode,code)==0&&p.flag=='*')
{
p.flag=' ';
//position put pointer
pos=count*sizeof(p);
file.seekp(pos,ios::beg);
file.write((char*)&p,sizeof(p));
file.close();
return ;
}
count++;
}
file.close();
cout<<endl<<"No Employee In File With Code: "<<code;
cout<<endl<<"Press Any Key...";
getchar();
}
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