file handling read and write with example

1. <pre><div class="text_to_html">Filing
- Basic Operation
- Open
- Read/Write
- Close
- Header File
fstream
- Read
- ifstream
- Write
- ofstream
- Modes
- in
- input
- out
- output
- app
- append
******************************************************
Example 1: Writing data into a file
#include <iostream>
#include <fstream>
using namespace std;
int main(){
ofstream out;
out.open("C14.txt", ios::app);
char array[25];
cin >> array;
out << array << endl;
out.close();
return 0;
}
*****************************************************
Example 2: Reading from File
#include <iostream>
#include <fstream>
using namespace std;
int main(){
ifstream in;
in.open("C14.txt", ios::in);
char array[25];
while(!in.eof()){
in >> array;
cout << array << endl;
}
in.close();
return 0;
}
*****************************************************
Example 3: Reading data on file using functions
#include <iostream>
#include <fstream>
using namespace std;
void readData(ifstream &in){
char array[25];
while(!in.eof()){
in >> array;
cout << array << endl;

2. }
}
int main(){
ifstream in;
in.open("C14.txt", ios::in);
readData(in);
in.close();
return 0;
}
*****************************************************
Example 4: Writing data into a file using functions
#include <iostream>
#include <fstream>
using namespace std;
void writeData(ofstream &out, char array[]){
out << array << endl;
}
int main(){
ofstream out;
out.open("C14.txt", ios::app);
char array[25];
cin >> array;
writeData(out, array);
out.close();
return 0;
}
*****************************************************
Example 5: Reading and writing the attriubtes of ColdDrink
#include <iostream>
#include <fstream>
#include <string.h>
using namespace std;
struct ColdDrink{
int price;
char name[10];
float quantity;
};
void writeData(ofstream &out, ColdDrink d){
out << d.name << "t";
out << d.price << "t";
out << d.quantity << endl;
}
void readData(ifstream &in, ColdDrink &d){
in >> d.name;
in >> d.price;
in >> d.quantity;
}
int main(){
ofstream output;
output.open("ColdDrink.txt", ios::out);
ifstream input;
input.open("ColdDrink.txt", ios::in);
ColdDrink d1;
strcpy(d1.name, "Fanta");

3. d1.price = 45;
d1.quantity = 0.5f;
writeData(output, d1);
ColdDrink cd;
readData(input, cd);
cout << "Name of the Drink: " << cd.name << endl;
cout << "Price of the Drink: " << cd.price << endl;
cout << "Quantity of the Drink: " << cd.quantity << endl;
output.close();
input.close();
return 0;
}</div></pre>
#include <iostream>
#include <fstream>
#include <string.h>
using namespace std;
struct ColdDrink{
int price;
char name[10];
float quantity;
int expire;
};
void writeData(ofstream &write, ColdDrink &d){
write << d.name << "t";
write << d.price << "t";
write << d.quantity << endl;
write << d.expire << endl;
}
void readData(ifstream &read, ColdDrink &d){
read >> d.name;
read >> d.price;
read >> d.quantity;
read >> d.expire;
}
int main(){
ofstream writeintofile;
writeintofile.open("ColdDrink.txt", ios::out);
ifstream readintofile;

4. readintofile.open("ColdDrink.txt", ios::in);
ColdDrink drink;
strcpy(drink.name, "PEPSI");
drink.price = 45;
drink.quantity = 0.5f;
drink.expire = 2018;
writeData(writeintofile, drink);
ColdDrink colddrink;
readData(readintofile, colddrink);
cout << "Name of the Drink: " << colddrink.name << endl;
cout << "Price of the Drink: " <<colddrink .price << endl;
cout << "Quantity of the Drink: " << colddrink.quantity << endl;
cout << "expiry of the Drink: " << colddrink.expire << endl;
writeintofile.close();
readintofile.close();
return 0;
}