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

namespace _5_71
{
    class Program
    {
        static void Main(string[] args)
        {
            string path = @"E:\c#\c#_net\15_71\test.txt";
            //appendtext();
            if (!File.Exists(path))                                    
            {
                // Create a file to write to.
                using (StreamWriter sw = File.CreateText(path))
                {
                    sw.WriteLine("Hello");
                    sw.WriteLine("And");
                    sw.WriteLine("Welcome");
                }
            }

            // This text is always added, making the file longer over time
            // if it is not deleted.
            using (StreamWriter sw = File.AppendText(path))
            {
                sw.WriteLine("This");
                sw.WriteLine("is Extra");
                sw.WriteLine("Text");
            }

            // Open the file to read from.
            using (StreamReader sr = File.OpenText(path))
            {
                string s = "";
                while ((s = sr.ReadLine()) != null)
                {
                    Console.WriteLine(s);
                }
            }

        }

      }
}

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