files & web

Program.cs

using System.Net;
using System.Text;

namespace ConsoleEvents
{
    public class FileDownloader
    {
        public event EventHandler<double>? ProgressChanged;
        public event EventHandler<string>? DownloadCompleted;

        public void DownloadFile(string url, string path)
        {
            var request = (HttpWebRequest)WebRequest.Create(url);
            using var response = (HttpWebResponse)request.GetResponse();
            long totalBytes = response.ContentLength;
            using var stream = response.GetResponseStream();
            using var fileStream = new FileStream(path, FileMode.Create);
            var buffer = new byte[8192];
            long totalRead = 0;
            int read;
            while ((read = stream.Read(buffer, 0, buffer.Length)) > 0)
            {
                fileStream.Write(buffer, 0, read);
                totalRead += read;
                if (totalBytes > 0)
                {
                    double progress = (totalRead / (double)totalBytes) * 100;
                    ProgressChanged?.Invoke(this, progress);
                }
            }
            DownloadCompleted?.Invoke(this, path);
        }
    }

    public class FileCopier
    {
        public event EventHandler<double>? ProgressChanged;
        public event EventHandler<string>? CopyCompleted;

        public void CopyFile(string source, string dest)
        {
            if (!File.Exists(source))
            {
                File.WriteAllText(source, new string('A', 100000));
            }
            long totalBytes = new FileInfo(source).Length;
            using var srcStream = File.OpenRead(source);
            using var dstStream = File.Create(dest);
            var buffer = new byte[8192];
            long totalRead = 0;
            int read;
            while ((read = srcStream.Read(buffer, 0, buffer.Length)) > 0)
            {
                dstStream.Write(buffer, 0, read);
                totalRead += read;
                double progress = (totalRead / (double)totalBytes) * 100;
                ProgressChanged?.Invoke(this, progress);
            }
            CopyCompleted?.Invoke(this, dest);
        }
    }

    class Program
    {
        static void Main()
        {
            Console.OutputEncoding = Encoding.UTF8;

            var downloader = new FileDownloader();
            var copier = new FileCopier();

            downloader.ProgressChanged += (sender, progress) =>
                Console.Write($"\rЗавантаження: {progress:F1}%");
            downloader.DownloadCompleted += (sender, path) =>
                Console.WriteLine($"\nЗавантаження завершено! Файл: {path}");

            copier.ProgressChanged += (sender, progress) =>
                Console.Write($"\rКопіювання: {progress:F1}%");
            copier.CopyCompleted += (sender, path) =>
                Console.WriteLine($"\nКопіювання завершено! Файл: {path}");

            downloader.DownloadFile("https://www.polly.com.ua/test/1Gb", "downloaded.txt");
            copier.CopyFile("downloaded.txt", "copy.txt");

            Console.ReadKey(); 
        }
    }
}