How to take a screenshot of a Full Size window in C#

publicclass ScreenShot
  {///<summary>/// Captures the screenshot of the entire desktop///</summary>///<returns>Image object containing the screenshot of the desktop</returns>private Image CaptureDesktop()
    {return CaptureWindow(User32.GetDesktopWindow());
    }public Image CaptureAciveWindow()
    {return CaptureWindow(User32.GetForegroundWindow());
    }///<summary>/// An Internal method, that captures the screenshot of any given Application window, given its Handle.///</summary>///<param name="handle">The handle of the window you want to Capture</param>///<returns>An Image object containing the screenshot of the active application window</returns>private Image CaptureWindow(IntPtr handle)
    {// get te hDC of the target window
      IntPtr hdcSrc = User32.GetWindowDC(handle);// get the size
      User32.RECT windowRect = new User32.RECT();
      User32.GetWindowRect(handle, ref windowRect);int width = windowRect.right - windowRect.left;int height = windowRect.bottom - windowRect.top;// create a device context we can copy to
      IntPtr hdcDest = GDI32.CreateCompatibleDC(hdcSrc);// create a bitmap we can copy it to,// using GetDeviceCaps to get the width/height
      IntPtr hBitmap = GDI32.CreateCompatibleBitmap(hdcSrc, width, height);// select the bitmap object
      IntPtr hOld = GDI32.SelectObject(hdcDest, hBitmap);// bitblt over
      GDI32.BitBlt(hdcDest, 0, 0, width, height, hdcSrc, 0, 0, GDI32.SRCCOPY);// restore selection
      GDI32.SelectObject(hdcDest, hOld);// clean up 
      GDI32.DeleteDC(hdcDest);
      User32.ReleaseDC(handle, hdcSrc);// get a .NET image object for it
      Image img = Image.FromHbitmap(hBitmap);// free up the Bitmap object
      GDI32.DeleteObject(hBitmap);return img;
    }///<summary>/// Helper class containing Gdi32 API functions///</summary>privateclass GDI32
    {publicconstint SRCCOPY = 0x00CC0020; // BitBlt dwRop parameter

      [DllImport("gdi32.dll")]publicstaticexternbool BitBlt(IntPtr hObject, int nXDest, int nYDest,int nWidth, int nHeight, IntPtr hObjectSource,int nXSrc, int nYSrc, int dwRop);
      [DllImport("gdi32.dll")]publicstaticextern IntPtr CreateCompatibleBitmap(IntPtr hDC, int nWidth,int nHeight);
      [DllImport("gdi32.dll")]publicstaticextern IntPtr CreateCompatibleDC(IntPtr hDC);
      [DllImport("gdi32.dll")]publicstaticexternbool DeleteDC(IntPtr hDC);
      [DllImport("gdi32.dll")]publicstaticexternbool DeleteObject(IntPtr hObject);
      [DllImport("gdi32.dll")]publicstaticextern IntPtr SelectObject(IntPtr hDC, IntPtr hObject);
    }///<summary>/// Helper class containing User32 API functions///</summary>privateclass User32
    {
      [StructLayout(LayoutKind.Sequential)]publicstruct RECT
      {publicint left;publicint top;publicint right;publicint bottom;
      }

      [DllImport("user32.dll")]publicstaticextern IntPtr GetDesktopWindow();
      [DllImport("user32.dll")]publicstaticextern IntPtr GetWindowDC(IntPtr hWnd);
      [DllImport("user32.dll")]publicstaticextern IntPtr ReleaseDC(IntPtr hWnd, IntPtr hDC);
      [DllImport("user32.dll")]publicstaticextern IntPtr GetWindowRect(IntPtr hWnd, ref RECT rect);///<summary>/// Gets the Handle for current active window///</summary>///<returns>Active windows Handle</returns>
      [DllImport("user32.dll")]publicstaticextern IntPtr GetForegroundWindow();
    }
  }