How do I save console output to update an existing string?

Question

I have a program that takes an input from the user (dnaInput). Then I have a Console output that prints a DNA strand. I want this console output to be saved to the dnaInput string to update it.

Here is my code:

namespace ConsoleApp2
{
    class Program
    {
        public static string dnaInput;

        public static void Main(string[] args)
        {

            // Variables

            bool showMenu = true; // Boolean variable for the main menu (for while loop)

            while (showMenu) // Main menu loop, this makes the program go back to the main menu after any operation
            {
                showMenu = MainMenu();
            }

        }

        private static bool MainMenu()
        {
            Console.Clear();
            Console.WriteLine("Loaded Main Strand: "+dnaInput+"\n"); // *** IMPORTANT *** THIS SHOWS THE LATEST UPDATE OF THE MAIN DNA STRAND. THIS IS WHAT WE ARE TRYING TO FIX.
            Console.WriteLine(@"----Life on Mars---- DEBUG FOR MAIN STRAND" + "\n");
            Console.WriteLine("Choose an option:");
            Console.WriteLine("1) Input DNA Strand 1 by keyboard");
            Console.WriteLine("1) Input DNA Strand 2 by keyboard");
            Console.WriteLine("0) Exit");
            Console.Write("\r\nSelect an option: ");


            switch (Console.ReadLine())
            {

                case "1":
                    FirstCodon();
                    return true;

                case "2":
                    SecondCodon();
                    return true;

                case "0":
                    return false;

                default:
                    return true;
            }
        }

        public static void FirstCodon() // this runs when you select 1 on the main menu
        {
            Console.WriteLine("Input DNA Strand 1: ");
            dnaInput = Console.ReadLine();

        }
   
        public static void SecondCodon() // this runs when you select 2 on the main menu
        {
            Console.Write("save this to the string -> dnaInput");
            // what to do after this?
        }
    }
}

I tried StreamWriter to send the console output to a text file but this didn't work. I tried this:

FileStream filestream = new FileStream("out.txt", FileMode.Create);
var streamwriter = new StreamWriter(filestream);
streamwriter.AutoFlush = true;
Console.SetOut(streamwriter);
Console.SetError(streamwriter);

Instead of taking the console output I want, it took the console output of my main menu.

Please clarify your specific problem or provide additional details to highlight exactly what you need. As it's currently written, it's hard to tell exactly what you're asking. — Community, Nov 27 '22 at 15:45

score 0 · Accepted Answer · answered Nov 27 '22 at 13:27

First Console.SetOut then Console.Write("save this to the string -> dnaInput");

private static void SecondCodon() // this runs when you select 2 on the main menu
    {
        var oldOut = Console.Out;

        using var fileStream = new FileStream("out.txt", FileMode.Create);
        using var streamWriter = new StreamWriter(fileStream);
        Console.SetOut(streamWriter);
        Console.SetError(streamWriter);

        Console.Write("save this to the string -> dnaInput");

        Console.SetOut(oldOut);
        Console.SetError(oldOut);
    }

Look also at this answers: Mirroring console output to a file

How do I save console output to update an existing string?

1 Answers1