Checking if a file opened successfully with ifstream

Question

I have the following that will open a file for reading. However, I want to check to make sure that the file was open successfully, so I am using the fail to see if the flags

Answer 1

you can also use std::ifstream::is_open. Returns true if a file is open and associated with this stream object.

// ifstream::is_open
#include      // std::cout
#include       // std::ifstream

int main () {
  std::ifstream ifs ("test.txt");

  if (ifs.is_open()) {
    // print file:
    char c = ifs.get();
    while (ifs.good()) {
      std::cout << c;
      c = ifs.get();
    }
  }
  else {
    // show message:
    std::cout << "Error opening file";
  }

  return 0;
}

http://www.cplusplus.com/reference/fstream/ifstream/is_open/