private void button2_Click(object sender, EventArgs e)
        {
            if (folderBrowserDialog1.ShowDialog() == DialogResult.OK)
            {
                DirectoryInfo dir = new DirectoryInfo(folderBrowserDialog1.SelectedPath);
                FileInfo[] files = dir.GetFiles("*.html");
                for (int i = 0; i < files.Length; i++)
                {
                    System.IO.StreamReader sr = new System.IO.StreamReader(files[i].DirectoryName+"\\"+files[i].ToString());
                    NSoup.Nodes.Document doc = NSoup.NSoupClient.Parse(sr.ReadToEnd());
                    try
                    {
                        sr.Dispose();
                        File.Delete(files[i].DirectoryName + "\\" + files[i].ToString());
                        using (StreamWriter sw = new StreamWriter(files[i].DirectoryName+"\\"+files[i].ToString(), false, System.Text.Encoding.GetEncoding("UTF-8"))) //保存地址
                        {
                            sw.WriteLine(doc.ToString());
                            sw.Flush();
                            sw.Close();
                        }
                    }
                    catch
                    {

                    } 
                }
                Application.Exit();
            }
        }