.a file c++ code example

Example 1: file c++

#include <iostream>
#include <string>
#include <fstream> //write and read
//#include <ifstream> //read
//#include <ofstream> //write

int main () {
  std::string line;
  std::ofstream myfileWrite;
  std::ifstream myfileRead;
  myfileWrite.open("example.txt");
  myfileRead.open("example.txt");
  myfileWrite << "Writing this to a file.\n";
  while (getline(myfileRead,line)){
    std::cout << line << '\n';
  }
  myfileWrite.close();
  myfileRead.close();
  return 0;
}

Example 2: how to open an input file in c++

#include <fstream>

ifstream file_variable; //ifstream is for input from plain text files
file_variable.open("input.txt"); //open input.txt

file_variable.close(); //close the file stream
/*
Manually closing a stream is only necessary
if you want to re-use the same stream variable for a different
file, or want to switch from input to output on the same file.
*/
_____________________________________________________
//You can also use cin if you have tables like so:
while (cin >> name >> value)// you can also use the file stream instead of this
{
 cout << name << value << endl;
}
_____________________________________________________
//ifstream file_variable; //ifstream is for input from plain text files
ofstream out_file;
out_file.open("output.txt");

out_file << "Write this scentence in the file" << endl;

Example 3: fstream read write mode

stream file;
file.open(fileName,ios::in | ios::out);