C++ Writing to file
In file handling, write() function is used to write data into the file. The write() uses ofstream or fstream library to write into the file.
Syntax
file-stream-class file-stream-object; file-stream-object.write((char *)&var , sizeof (var));
The write() takes two arguments. The first argument is the address of variable var and the second argument is the size of variable var in bytes.
Example
ofstream outfile; outfile .write ((char*)&emp,sizeof(emp));
C++ File Handling write() Function Example
#include <iostream>
#include <fstream>
using namespace std;
class employee
{
private:
char name[30];
float salary;
public:
void getData(void)
{ cout<<"Enter name:";
cin.getline(name,sizeof(name));
cout<<"Enter salary:";
cin>>salary;
}
};
int main()
{
employee emp;
ofstream file;
file.open("employee.txt",ios::out);//open file in write mode
if(!file)
{
cout<<"File not found"<<endl;
return 0;
}
cout<<"File created successfully."<<endl;
emp.getData();
file.write((char*)&emp,sizeof(emp)); //write into file
file.close(); //close the file
cout<<"File save and closed succesfully."<<endl;
return 0;
}
Output:
