C# .net screencapture à partir du site caché.

Question

Un graphique est généré dans une page Web. J'essaie de faire une capture d'écran avec du code C#. J'ai essayé le code ci-dessous. Cela a fonctionné plusieurs fois et maintenant je reçois l'erreur "index était hors de portée, doit être non négatif et moins que la taille de la collection".

Toute aide ou conseil est appréciée. Merci d'avance.

System.Drawing.Bitmap bitMap = null; 
    static AutoResetEvent autoEvent; 
    public void DownloadAsImage(string title, string location) 
    { 
     autoEvent = new AutoResetEvent(false); 

     Uri url = HttpContext.Current.Request.Url; 
     string RootUrl = url.AbsoluteUri.Replace(url.PathAndQuery, string.Empty); 

     //ApartmentState:specifies the state of a system.threading.thread 
     //STA:Thread will create and enter a single-threaded apartment 
     Thread t = new Thread(CaptureWebPageToDisplay); 
     t.SetApartmentState(ApartmentState.STA); 
     if (title == "PieGraph" && location == "0") 
     { 
      t.Start(RootUrl + "/_Layouts/AppPage/Reports/TotalGraphPage.aspx?isdlg=1"); 
      Thread.Sleep(30000); 
     } 
     else 
     { 
      t.Start(RootUrl + "/_Layouts/AppPage/Reports/GraphPage.aspx?isdlg=1&Title=" + title + "&Location=" + location); 
      Thread.Sleep(10000); 
     } 
     autoEvent.Set(); 

     HttpContext.Current.Response.ContentType = "image/jpeg"; 
     string targetFolder = Server.MapPath(@".\GraphImages\") + title + ".Jpeg"; 

     try 
     { 
      bitMap.Save(targetFolder); 
      bitMap.Dispose(); 
     } 
     catch(Exception ex){ 
      DBLogger.ExpandException(ex); 
      if (bitMap != null) 
      { 
       bitMap.Dispose(); 
      } 
     } 

    } 
    public void CaptureWebPageToDisplay(object URL) 
    { 
     // create a hidden web browser, which will navigate to the page 
     System.Windows.Forms.WebBrowser web = new System.Windows.Forms.WebBrowser(); 
     // Full web browser 
     web.Dock = System.Windows.Forms.DockStyle.Fill; 
     web.Size = new System.Drawing.Size(1000, 800); 
     // we don't want scrollbars on our image 
     web.ScrollBarsEnabled = false; 
     // don't let any errors shine through 
     web.ScriptErrorsSuppressed = true; 
     // let's load up that page! 
     web.Navigate((string)URL); 

     // wait until the page is fully loaded 
     while (web.ReadyState != System.Windows.Forms.WebBrowserReadyState.Complete) 
      System.Windows.Forms.Application.DoEvents(); 
     System.Threading.Thread.Sleep(5000); // allow time for page scripts to update 


     // the appearance of the page 
     // set the size of our web browser to be the same size as the page 
     int width = web.Document.Body.ScrollRectangle.Width; 
     int height = web.Document.Body.ScrollRectangle.Height; 
     web.Width = width; 
     web.Height = height; 

     // a bitmap that we will draw to 
     System.Drawing.Bitmap bmp = new System.Drawing.Bitmap(width, height); 

     // change background color to white, just in case 
     System.Drawing.Graphics g = System.Drawing.Graphics.FromImage(bmp); 
     g.Clear(System.Drawing.Color.White); 

     // create rectangle. 
     System.Drawing.Rectangle rect = new System.Drawing.Rectangle(20, 0, width, height); 

     // draw the web browser to the bitmap 
     web.DrawToBitmap(bmp, rect); 
     bitMap = bmp; 
    } 

Answer 1

Je pense que le code suivant pour capturer un écran pourrait aider:

 public static void CaptureScreen(double x, double y, double width, double height) 
     { 
      int ix, iy, iw, ih; 
      ix = Convert.ToInt32(x); 
      iy = Convert.ToInt32(y); 
      iw = Convert.ToInt32(width); 
      ih = Convert.ToInt32(height); 
      Bitmap image = new Bitmap(iw, ih, 
        System.Drawing.Imaging.PixelFormat.Format32bppArgb); 
      Graphics g = Graphics.FromImage(image); 
      g.CopyFromScreen(ix, iy, ix, iy, 
        new System.Drawing.Size(iw, ih), 
        CopyPixelOperation.SourceCopy); 
      // Download Image 
      image.Save(FileName, ImageFormat.Png); 
     }