下面的C++代码将用户输入的信息写入到afile.dat，然后再通过程序读取出来输出到屏幕

#include <fstream>
#include <iostream>
using namespace std;
  
int main ()
{
     
   char data[100];
 
   // open a file in write mode.
   ofstream outfile;
   outfile.open("afile.dat");
 
   cout << "Writing to the file" << endl;
   cout << "Enter your name: ";
   cin.getline(data, 100);
 
   // write inputted data into the file.
   outfile << data << endl;
 
   cout << "Enter your age: ";
   cin >> data;
   cin.ignore();
    
   // again write inputted data into the file.
   outfile << data << endl;
 
   // close the opened file.
   outfile.close();
 
   // open a file in read mode.
   ifstream infile;
   infile.open("afile.dat");
  
   cout << "Reading from the file" << endl;
   infile >> data;
 
   // write the data at the screen.
   cout << data << endl;
    
   // again read the data from the file and display it.
   infile >> data;
   cout << data << endl;
 
   // close the opened file.
   infile.close();
 
   return 0;
}

$./a.out
Writing to the file
Enter your name: Zara
Enter your age: 9
Reading from the file
Zara
9