sdtgyh

static void Main(string[] args)
        {
            string scoresDir = @"F:\Documents\Computing\Projects\File management\scores\highScores.dll";
            if (File.Exists(scoresDir) == false)
            {
                //Create one.
                using (File.Create(scoresDir)) { }
            }
            Console.WriteLine("This is a file-management based quiz application.");
            Console.WriteLine("Press ENTER to begin.");
            Console.ReadKey();
            Console.Clear();
            Console.WriteLine();
            Console.WriteLine("Please select which quiz you'd like to answer: ");
            Console.WriteLine();
            DirectoryInfo dinfo = new DirectoryInfo(@"F:\Documents\Computing\Projects\File management\");
            FileInfo[] quizzes = dinfo.GetFiles("*.txt");
            int counter = 1;
            foreach (FileInfo quiz in quizzes)
            {
                int index = quiz.Name.IndexOf(".");
                string fileName = quiz.Name.Substring(0, index);
                Console.WriteLine("[" + counter + "] " + fileName);
                counter = counter + 1;
            }
            Console.WriteLine();
            Console.Write("Selection > ");
            int quizSelected = int.Parse(Console.ReadLine());
            Console.Clear();
            string quizSelectedName = quizzes[quizSelected - 1].Name.ToString().Substring(0, quizzes[quizSelected - 1].Name.ToString().IndexOf('.'));
            Console.WriteLine();
            Console.WriteLine("Starting your selected quiz: " + quizSelectedName + "!");
            string quizDir = @"F:\Documents\Computing\Projects\File management\" + quizSelectedName + ".txt";
            Console.WriteLine("Press ENTER to start!");
            Console.ReadKey();

            // Formatting guide.
            // Files are formatted as follows:
            //
            // What is the answer to question 1?;Answer1
            // What is the answer to question 2?;Answer2
            // What is the answer to question 3?;Answer3

            StreamReader quizReader = new StreamReader(quizDir);
            int lines = File.ReadAllLines(quizDir).Count();
            int score = 0;
            for (int i = 0; i < lines; i++)
            {
                Console.Clear();
                string thisLine = quizReader.ReadLine();
                string thisQuestion = thisLine.Substring(0, thisLine.IndexOf(";"));
                string thisAnswer = thisLine.Substring(thisLine.IndexOf(";") + 1).ToLower();
                Console.WriteLine();
                Console.WriteLine("Current Score: {0}", score);
                Console.WriteLine("You've answered " + i + " questions so far.");
                Console.WriteLine();
                Console.WriteLine("------ QUESTION " + (i + 1) + " ------");
                Console.WriteLine();
                Console.WriteLine("Q > " + thisQuestion);
                Console.Write("A > ");
                string givenAnswer = Console.ReadLine().ToLower();
                if (givenAnswer == thisAnswer)
                {
                    // Correct!
                    score = score + 1;
                    Console.WriteLine();
                    Console.WriteLine("Answer correct! :)");
                }
                else
                {
                    // Incorrect!
                    Console.WriteLine();
                    Console.WriteLine("Answer incorrect, sorry! :(");
                }
                Console.ReadKey();
            }
            Console.Clear();
            Console.WriteLine();
            Console.WriteLine("Quiz \"" + quizSelectedName + "\" completed!");
            float Percentage = ((score / lines) * 100);
            Console.WriteLine("You scored " + score + "/" + lines + " (" + Percentage + "%)!");
            Console.WriteLine();
            Console.Write("Looking to save your score? Enter \"Y\" for yes, and \"N\" for no: ");
            string gAnswer = Console.ReadLine().ToLower();
            if (gAnswer == "y")
            {
                Console.Clear();
                Console.WriteLine();
                Console.Write("Enter a name to save your score ("+Percentage+"%) under: ");
                string savedName = Console.ReadLine();
                savedName = savedName.Replace(";", "-");
                savedName = savedName.Replace(",", "-");
                // High score saving etc.
                // Format:
                //
                // Quiz name;Person1,Score
                // Quiz name;Person2,Score
                StreamReader scoresReader = new StreamReader(scoresDir);
                List<string> scoresLines = File.ReadLines(scoresDir).ToList();
                foreach (string scores in scoresLines)
                {
                    if (scores.Substring(0, scores.IndexOf(";")) == quizSelectedName)
                    {
                        //This is the quiz being played.
                        Console.WriteLine(scores);
                        Console.WriteLine(scores.IndexOf(";") + 1);
                        Console.WriteLine(scores.IndexOf(","));
                        Console.WriteLine(scores.Substring(scores.IndexOf(";") + 1, (scores.IndexOf(",")- scores.IndexOf(";") + 1)));
                        if (scores.Substring(scores.IndexOf(";") + 1, (scores.IndexOf(",") - scores.IndexOf(";") + 1)) == savedName)
                        {
                            //This is same playername as a previous score.
                            string oldScore = scores.Substring(scores.IndexOf(",") + 1);
                            if (float.Parse(oldScore) < Percentage) {
                                //New highscore.
                                Console.WriteLine("Congratulations! Your score of "+Percentage+"% is a new highscore for this user!");
                                var newScoresList = scoresLines.Select(s => s.Replace((quizSelectedName + ";" + savedName + "," + oldScore), (quizSelectedName + ";" + savedName + "," + Percentage))).ToList();
                                File.WriteAllText(scoresDir, String.Empty);
                                TextWriter scoresWriter = new StreamWriter(scoresDir);
                                foreach (string s in newScoresList)
                                {
                                    scoresWriter.WriteLine(s);
                                }
                                scoresWriter.Close();
                            }
                        }
                    }
                }
            }
            else if (gAnswer == "n")
            {

            }
            else
            {

            }
            // End of program.
            Console.WriteLine("Application completed. Press ENTER to exit.");
            Console.ReadKey();
        }