Example 1
--------------------------------------------------------------
#include <iostream>
#include <fstream>
using namespace std;

int main() {
  // Create and open a text file
  ofstream MyFile("filename.txt");

  // Write to the file
  MyFile << "Files can be tricky, but it is fun enough!";

  // Close the file
  MyFile.close();
}


Example 2
------------------------------------------------------------
#include <iostream>
#include <fstream>
using namespace std;

int main() {

// Create a text string, which is used to output the text file
string myText;
char ch;
// Read from the text file
ifstream MyReadFile("filename.txt");

// Read by using getline() function to read the file line by line
cout << "Read by getline()" << endl;
while (getline (MyReadFile, myText)) {
  // Output the text from the file
  cout << myText << endl;
}
MyReadFile.close();
ifstream MyReadFile2("filename.txt");

cout << "Read character by character" << endl;
while( MyReadFile2 >> ch){
  // output the character
  cout << ch;
}
// Close the file
MyReadFile2.close();

}


Example 3
------------------------------------------------------------
#include <iostream>
#include <fstream>
using namespace std;

int main() {

  string filename;
  fstream myfile;

  cout << "Enter filename: ";
  cin >> filename;

  const char* fcs = filename.c_str();

  myfile.open(fcs,ios::app);
  myfile << "This is a sentence" << endl;

  // Close the file
  myfile.close();


}