How to encrypt a message written in a file entered by the user?

Question

        required.get(c);
    }
    cout << "The encryption is over";
    required.close();
    destined.close();
}

This program should encrypt/decrypt a message in a file, that the user should mention. It should have 3 functions, one to check the existence of the input file, the second should encrypt/decrypt each character and one to encrypt/decrypt the whole file. The thing is that the it keeps saying "The file does not exist". I don't know how to read it. Second problem is that the function to encrypt (encFile) does not work.

Answer 1

The thing is that the it keeps saying "The file does not exist". I don't know how to read it.

To fix this behavior change your checkExistingFile() function as follows:

 bool  checkExistingFile(string& inFile)
 {
      ifstream required;
      required.open(inFile.c_str());
      while(required.fail())
      {
           cout<< "The file does not exist, please enter another file " <<
                  "(leave empty to abort)"<< endl;
           cin >> inFile;
           if(infile.empty()) { return false; }
           required.open(inFile.c_str());
      }

      return true;
 }

May be you should consider to give the user a chance to break the loop (eg giving an empty file name), and return false then.

As others and you yourself mentioned there, are other problems with your code, I don't answer here.