using System.IO;
  using System.Drawing;
  using System.Threading;
  using System.Windows.Forms;
  public class WebSiteThumbnail
  {
  Bitmap m_Bitmap;
  string m_Url;
  int m_BrowserWidth, m_BrowserHeight, m_ThumbnailWidth, m_ThumbnailHeight;
  public WebSiteThumbnail(string Url, int BrowserWidth, int BrowserHeight, int ThumbnailWidth, int ThumbnailHeight)
  {
  m_Url = Url;
  m_BrowserHeight = BrowserHeight;
  m_BrowserWidth = BrowserWidth;
  m_ThumbnailWidth = ThumbnailWidth;
  m_ThumbnailHeight = ThumbnailHeight;
  }
  public static Bitmap GetWebSiteThumbnail(string Url, int BrowserWidth, int BrowserHeight, int ThumbnailWidth, int ThumbnailHeight)
  {
  WebSiteThumbnail thumbnailGenerator = new WebSiteThumbnail(Url, BrowserWidth, BrowserHeight, ThumbnailWidth, ThumbnailHeight);
  return thumbnailGenerator.GenerateWebSiteThumbnailImage();
  }
  public Bitmap GenerateWebSiteThumbnailImage()
  {
  Thread m_thread = new Thread(new ThreadStart(_GenerateWebSiteThumbnailImage));
  m_thread.SetApartmentState(ApartmentState.STA);
  m_thread.Start();
  m_thread.Join();
  return m_Bitmap;
  }
  private void _GenerateWebSiteThumbnailImage()
  {
  WebBrowser m_WebBrowser = new WebBrowser();
  m_WebBrowser.ScrollBarsEnabled = false;
  m_WebBrowser.Navigate(m_Url);
  m_WebBrowser.DocumentCompleted += new WebBrowserDocumentCompletedEventHandler(WebBrowser_DocumentCompleted);
  while (m_WebBrowser.ReadyState != WebBrowserReadyState.Complete)
  Application.DoEvents();
  m_WebBrowser.Dispose();
  }
  private void WebBrowser_DocumentCompleted(object sender, WebBrowserDocumentCompletedEventArgs e)
  {
  WebBrowser m_WebBrowser = (WebBrowser)sender;
  m_WebBrowser.ClientSize = new Size(this.m_BrowserWidth, this.m_BrowserHeight);
  m_WebBrowser.ScrollBarsEnabled = false;
  m_Bitmap = new Bitmap(m_WebBrowser.Bounds.Width, m_WebBrowser.Bounds.Height);
  m_WebBrowser.BringToFront();
  m_WebBrowser.DrawToBitmap(m_Bitmap, m_WebBrowser.Bounds);
  m_Bitmap = (Bitmap)m_Bitmap.GetThumbnailImage(m_ThumbnailWidth, m_ThumbnailHeight, null, IntPtr.Zero);
  }
  }
  Bitmap m_Bitmap = WebSiteThumbnail.GetWebSiteThumbnail("这里是html的连接地址", 990, 2798, 990, 2798);
  MemoryStream ms = new MemoryStream();
  m_Bitmap.Save(ms, System.Drawing.Imaging.ImageFormat.Png);//JPG、GIF、PNG等均可
  byte[] buff = ms.ToArray();
  Response.BinaryWrite(buff);
  System.Drawing.Image img = byteArrayToImage(buff);
  string url = "图片保存路径.png";
  img.Save(HttpContext.Current.Server.MapPath(url));