.NET 4.x Написание службы для создания скриншотов - C#

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Diagnostics;
using System.Linq;
using System.ServiceProcess;
using System.Text;
using System.Threading;
using System.IO;
using System.Drawing.Imaging;
namespace my_service
{
 
    public partial class Service1 : ServiceBase
    {
        private StreamWriter file;
        private System.Timers.Timer timer1;
        public Service1()
        {
            InitializeComponent();
        }
 
        static /*public*/ string GenerateRandomJpegName()
        {
            return GenerateRandomString() + ".jpg";
        }
 
        static string GenerateRandomString()
        {
            bool UseSigns = true;
            bool UseUpperLetters = true;
            bool UseLetters = true;
            int Length;
        NewLabel:
            try
            {
                Length = new Random(DateTime.Now.Millisecond - DateTime.Now.Second + new Random(DateTime.Now.Millisecond).Next(0, 100) / new Random(DateTime.Now.Millisecond - DateTime.Now.Second).Next(0, 10)).Next(0, 100);
            }
            catch { goto NewLabel; }
            string result = "C:/";
            try
            {
                int Seed = 0;
                char[] letters = { 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z' };
                char[] signs = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9' };
                List<char> keyWords = new List<char>();
                List<char> upperLetters = new List<char>();
                foreach (char c in letters)
                    upperLetters.Add(Convert.ToChar(c.ToString().ToUpper()));
                if (UseLetters)
                    foreach (char c in letters)
                        keyWords.Add(c);
                if (UseSigns)
                    foreach (char c in signs)
                        keyWords.Add(c);
                if (UseUpperLetters)
                    foreach (char c in upperLetters)
                        keyWords.Add(c);
                int MaxValue = keyWords.Count;
                for (int i = 0; i <= Length; i++)
                {
                    try
                    {
                        Random mainrand = new Random(Seed);
                        char RandChar = keyWords[mainrand.Next(0, MaxValue)];
                        result += RandChar;
                        Seed += DateTime.Now.Millisecond + Seed - new Random().Next(10) + new Random(DateTime.Now.Millisecond + 800 * 989 / 3).Next(10);
                    }
                    catch { continue; }
                }
            }
            catch { }
            return result;
        }
 
        protected override void OnStart(string[] args)
        {
            Bitmap bmp = new Bitmap(Screen.PrimaryScreen.Bounds.Width, Screen.PrimaryScreen.Bounds.Height);
            Graphics g = Graphics.FromImage(bmp);
            g.CopyFromScreen(0, 0, Screen.PrimaryScreen.Bounds.X, Screen.PrimaryScreen.Bounds.Y, Screen.PrimaryScreen.Bounds.Size, CopyPixelOperation.SourceCopy);
            bmp.Save(GenerateRandomJpegName(), ImageFormat.Jpeg);
 
            file = new StreamWriter(new FileStream("my_first_service.txt",
   System.IO.FileMode.Append));
            this.file.WriteLine("MyFirstService стартовал");
            this.file.Flush();
            //Создаем таймер и выставляем его параметры
            this.timer1 = new System.Timers.Timer();
            this.timer1.Enabled = true;
            //Интервал 10000мс - 10с.
            this.timer1.Interval = 100000;
            this.timer1.Elapsed +=
             new System.Timers.ElapsedEventHandler(this.timer1_Elapsed);
            this.timer1.AutoReset = true;
            this.timer1.Start();
 
        }
 
        protected override void OnStop()
        {
            this.timer1.Stop();
            this.file.WriteLine("MyFirstService остановлен");
            this.file.Flush();
            this.file.Close();
        }
        private void
        timer1_Elapsed(object sender, System.Timers.ElapsedEventArgs e)
        {
            //Записываем время в файл или делаем все, что хотим
            this.file.WriteLine(DateTime.Now.ToString("dd.MM.yyyy HH:mm:ss"));
            this.file.Flush();
      
        }
    }
}