My name
is
Jon Skeet

An Issue With Writing In A File In C#

I developed a simple program that asks the user if he wants to add a new record to a file or display all the records contained in the file, but I seem to have a problem in writing to the file. The file is created but still nothing is written in it. The reading function works fine since I wrote something in the file to see if it works.

Here is the code...

using System;
using System.IO;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace F01
{
    class Program
    {
        static int ID;
        static String Name;
        static void Main(string[] args)
        {
            FileStream MyFiler = new FileStream("MyFile.txt", FileMode.OpenOrCreate, FileAccess.ReadWrite);
            StreamReader FileReader = new StreamReader(MyFiler);
            StreamWriter FileWriter = new StreamWriter(MyFiler);
            Console.WriteLine("Please Select One Of The Following Options... ");
            Console.WriteLine("1. Enter A New Record In The File.");
            Console.WriteLine("2. Read All The Records From The File.");
            int Choice = int.Parse(Console.ReadLine());
            if (Choice == 1)
            {
                Console.WriteLine("Enter The ID: ");
                ID = int.Parse(Console.ReadLine());
                FileWriter.WriteLine(ID);
                Console.WriteLine("Enter The Name: ");
                Name = Console.ReadLine();
                FileWriter.WriteLine(Name);
            }

            else if (Choice == 2)
            {
                FileWriter.Close();
                String fileText = File.ReadAllText("MyFile.txt");
                for (int i = 0; i < fileText.Length; i++)
                {
                    Console.Write(fileText[i]);
                }
            }
            FileReader.Close();
        }
    }
}

Thanks in advance :)

You're not closing the writer in the only situation in which you're using it - "choice 1". Basically the data is being buffered, and lost when the process exits because you haven't closed the writer.

I would strongly advise you to:

Only open the file when you need to
Use local variables instead of class variables unless you need them in other methods
Use the File static methods to make all of this easier
Use using statements to clean up resources at the end of them (if you need a writer or a stream at all, that is...)
Break your code up into methods for separate operations
Name your variables in camelCase rather than PascalCase
Print your file a line at a time rather than a letter at a time

So for example:

using System;
using System.IO;

class Program
{
    const string FileName = "MyFile.txt";

    static void Main(string[] args)
    {
        Console.WriteLine("Please Select One Of The Following Options... ");
        Console.WriteLine("1. Enter A New Record In The File.");
        Console.WriteLine("2. Read All The Records From The File.");
        int choice = int.Parse(Console.ReadLine());
        switch (choice)
        {
            case 1:
                AddEntry();
                break;
            case 2:
                ReadFile();
                break;
            default:
                Console.WriteLine("Sorry, that's not a valid option");
                break;
        }
   }

   static void AddEntry()
   {
       Console.WriteLine("Enter the ID:");
       int id = int.Parse(Console.ReadLine());
       Console.WriteLine("Enter the name:");
       string name = Console.ReadLine();
       File.AppendAllLines(FileName, new[] { id.ToString(), name });
   }

   static void ReadFile()
   {
       foreach (var line in File.ReadLines(FileName))
       {
           Console.WriteLine(line);
       }
   }
}

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