rss reader

using System;
using System.Collections.Generic;
using System.Drawing;
using System.Windows.Forms;
using System.Xml;
using System.Xml.Xsl;
using System.Text;
using System.IO;
using System.Text.RegularExpressions;

namespace RSS_Reader
{

    public partial class MainForm : Form
    {
        string flFName = "feed_list.log"; // список лент, на которые мы подписались
        RSS rss; // текущая RSS-лента

        [STAThread]
        public static void Main(string[] args)
        {
            Application.EnableVisualStyles();
            Application.SetCompatibleTextRenderingDefault(false);
            Application.Run(new MainForm());
        }

        public MainForm()
        {
            InitializeComponent();

            if (File.Exists(flFName))
                lbFeeds.Items.AddRange(File.ReadAllLines(flFName));
        }

        void LoadFeed(string URL)
        {
            try {
                rss = new RSS(URL);
                wbIE.Navigate(Application.StartupPath+"\\"+rss.TransformToHTML());
            }catch(System.Net.WebException exc){
                MessageBox.Show(exc.Message,"Нет подключения к Интернет");
            }
        }



        void bNewClick(object sender, EventArgs e)
        {
            if (tbFeedURL.Text.Length>0)
            {
                string newURL = tbFeedURL.Text.Trim();
                lbFeeds.Items.Add(newURL);
                File.AppendAllText(flFName, newURL+"\n");
            }
        }

        void LbRSSClick(object sender, EventArgs e)
        {
            tbFeedURL.Text = lbFeeds.SelectedItem.ToString();
        }

        void LbRSSDoubleClick(object sender, EventArgs e)
        {
            tbFeedURL.Text = lbFeeds.SelectedItem.ToString();
            LoadFeed(tbFeedURL.Text);
        }

        void UpdateFeedListFile()
        {
            string bak_file = "feed_list.bak";
            try {
                if (File.Exists(bak_file)) File.Delete(bak_file);
                File.Move(flFName,bak_file);
                if (File.Exists(flFName)) File.Delete(flFName);
                foreach (string item in lbFeeds.Items)
                    File.AppendAllText(flFName,item+"\n");
            }catch (Exception e){
                MessageBox.Show(e.Message);
            }
        }

        void BEditClick(object sender, EventArgs e)
        {
            lbFeeds.Items[lbFeeds.SelectedIndex] = tbFeedURL.Text.Trim();
            UpdateFeedListFile();
        }

        void BDeleteClick(object sender, EventArgs e)
        {
            int idx = lbFeeds.SelectedIndex;
            lbFeeds.Items.RemoveAt(idx);
            if (idx>=lbFeeds.Items.Count) idx--;
            if (idx>=0) lbFeeds.SetSelected(idx, true);
            UpdateFeedListFile();
        }

        void SaveAsHTMLToolStripMenuItemClick(object sender, EventArgs e)
        {
            if (sfd1.ShowDialog()==DialogResult.OK)
                File.Move(Application.StartupPath+"\\feed.xls",sfd1.FileName);
        }

        private void MainForm_Load(object sender, EventArgs e)
        {

        }

        private void lbFeeds_SelectedIndexChanged(object sender, EventArgs e)
        {

        }

        private void label2_Click(object sender, EventArgs e)
        {

        }

        private void wbIE_ProgressChanged(object sender, WebBrowserProgressChangedEventArgs e)

        {
            try
            {
                progressBar1.Value = Convert.ToInt32(e.CurrentProgress);
                progressBar1.Maximum = Convert.ToInt32(e.MaximumProgress);
                //progressBar1.Visible = false;
            }
            catch (Exception ex)
            {

            }

        }

        private void wbIE_DocumentCompleted(object sender, WebBrowserDocumentCompletedEventArgs e)
        {

        }

        private void оПрограммеToolStripMenuItem_Click(object sender, EventArgs e)
        {
            About newForm = new About();
            newForm.Show();
        }

        private void pictureBox2_Click(object sender, EventArgs e)
        {

        }

        private void pictureBox2_MouseClick(object sender, MouseEventArgs e)
        {

        }

        private void MainForm_KeyPress(object sender, KeyPressEventArgs e)
        {
            if (e.KeyChar == (char)Keys.Back)       //Keys.(клавиша которая вам необходима)
            {
                button1_Click(sender, e);                   // button_Click кнопка по которой кликнуть надо
                e.Handled = true;
            }
        }

        private void button1_Click(object sender, EventArgs e)
        {

        }

        private void выходToolStripMenuItem_Click(object sender, EventArgs e)
        {
            Close();
        }
    }

    public class RSS
    {
        private string _URL;
        private XmlDocument doc;
        private string XML_FileName;
        private string HTML_FileName;
        private string XSL_FileName;
        public RSS(string URL): this(URL, "feed.xsl"){}
        public RSS(string URL, string XSLT_File)
        {
            if (! Directory.Exists("files")) Directory.CreateDirectory("files");
            XML_FileName = @"files\"+EscapeUrl(URL)+".xml";
            HTML_FileName = @"files\"+EscapeUrl(URL)+".htm";
            long dt=0;
            if (File.Exists(XML_FileName))
                dt = DateTime.Now.Ticks-File.GetCreationTime(XML_FileName).Ticks;
            XSL_FileName=XSLT_File;
            _URL = URL;
            doc = new XmlDocument();
            if (File.Exists(XML_FileName) && dt<3600e8)
                /* если лента уже была обновлена в течении предыдущего часа
                 * то загрузим её из локального файла */
                doc.Load(XML_FileName);
            else
                try
            {
                System.Net.WebClient client = new System.Net.WebClient();
                client.DownloadFile(_URL, XML_FileName);
                string sXML = File.ReadAllText(XML_FileName, Encoding.GetEncoding(1251));
                sXML = Regex.Replace(sXML, @"<\?xml-stylesheet.*\?>", "");
                sXML = Regex.Replace(sXML, @"<\w+\sxmlns:xsi.*\.xsd.?\s*>", "");
                sXML = Regex.Replace(sXML, @"<!DOCTYPE.*>", "");
                File.WriteAllText(XML_FileName, sXML, Encoding.GetEncoding(1251));
                doc.Load(XML_FileName);
            }
            catch (XmlException e)
            {
                MessageBox.Show(e.Message,"Ошибка загрузки или обработки XML");
            }
        }
        private string EscapeUrl(string s)
        {
            return s.Replace('/','_').Replace(".xml","").Replace("http:__","").Replace("www.","");
        }
        public XmlDocument NewsXML
        {
            get
            {
                return doc;
            }
        }
        public string TransformToHTML()
        {
            XslCompiledTransform xslt = new XslCompiledTransform();
            xslt.Load(XSL_FileName);
            xslt.Transform(XML_FileName, HTML_FileName);
            return HTML_FileName;
        }

    }
}