/// <summary>
/// Take a SnapShot of the application window
/// </summary>
/// <Remark>
/// http://www.codeproject.com/script/articles/list_articles.asp?userid=634640
///</Remark>
/// <param name="AppWndHandle"></param>
/// <param name="IsClientWnd"></param>
/// <param name="nCmdShow"></param>
/// <returns>Bitmap of application window </returns>
private static Bitmap TakeAppWndSnapShot(IntPtr AppWndHandle, bool IsClientWnd, ChessWin32API.WindowShowStyle nCmdShow)
{
if (AppWndHandle == IntPtr.Zero || !ChessWin32API.IsWindow(AppWndHandle) || !ChessWin32API.IsWindowVisible(AppWndHandle))
return null;
if (ChessWin32API.IsIconic(AppWndHandle))
ChessWin32API.ShowWindow(AppWndHandle, nCmdShow); //show it
if (!ChessWin32API.SetForegroundWindow(AppWndHandle))
return null; //can't bring it to front
System.Threading.Thread.Sleep(1000); //give it some time to redraw
RECT appRect;
bool res = IsClientWnd ? ChessWin32API.GetClientRect(AppWndHandle, out appRect) : ChessWin32API.GetWindowRect(AppWndHandle, out appRect);
if (!res || appRect.Height == 0 || appRect.Width == 0)
{
return null; //some hidden window
}
if (IsClientWnd)
{
Point lt = new Point(appRect.Left, appRect.Top);
Point rb = new Point(appRect.Right, appRect.Bottom);
ChessWin32API.ClientToScreen(AppWndHandle, ref lt);
ChessWin32API.ClientToScreen(AppWndHandle, ref rb);
appRect.Left = lt.X;
appRect.Top = lt.Y;
appRect.Right = rb.X;
appRect.Bottom = rb.Y;
}
// Intersect with the Desktop rectangle and get what's visible
IntPtr DesktopHandle = ChessWin32API.GetDesktopWindow();
RECT desktopRect;
ChessWin32API.GetWindowRect(DesktopHandle, out desktopRect);
RECT visibleRect;
if (!ChessWin32API.IntersectRect(out visibleRect, ref desktopRect, ref appRect))
{
visibleRect = appRect;
}
if (ChessWin32API.IsRectEmpty(ref visibleRect))
return null;
int Width = visibleRect.Width;
int Height = visibleRect.Height;
IntPtr hdcTo = IntPtr.Zero;
IntPtr hdcFrom = IntPtr.Zero;
IntPtr hBitmap = IntPtr.Zero;
try
{
Bitmap clsRet = null;
// get device context of the window...
hdcFrom = IsClientWnd ? ChessWin32API.GetDC(AppWndHandle) : ChessWin32API.GetWindowDC(AppWndHandle);
// create dc that we can draw to...
hdcTo = ChessWin32API.CreateCompatibleDC(hdcFrom);
hBitmap = ChessWin32API.CreateCompatibleBitmap(hdcFrom, Width, Height);
// validate...
if (hBitmap != IntPtr.Zero)
{
// copy...
int x = appRect.Left < 0 ? -appRect.Left : 0;
int y = appRect.Top < 0 ? -appRect.Top : 0;
IntPtr hLocalBitmap = ChessWin32API.SelectObject(hdcTo, hBitmap);
ChessWin32API.BitBlt(hdcTo, 0, 0, Width, Height, hdcFrom, x, y, ChessWin32API.SRCCOPY);
ChessWin32API.SelectObject(hdcTo, hLocalBitmap);
// create bitmap for window image...
clsRet = System.Drawing.Image.FromHbitmap(hBitmap);
}
//MessageBox.Show(string.Format("rect ={0} \n deskrect ={1} \n visiblerect = {2}",rct,drct,VisibleRCT));
//return...
return clsRet;
}
finally
{
// release ...
if (hdcFrom != IntPtr.Zero)
ChessWin32API.ReleaseDC(AppWndHandle, hdcFrom);
if (hdcTo != IntPtr.Zero)
ChessWin32API.DeleteDC(hdcTo);
if (hBitmap != IntPtr.Zero)
ChessWin32API.DeleteObject(hBitmap);
}
}
internal static extern bool EnumThreadWindows(uint dwThreadId, ChessWin32API.EnumThreadDelegate lpfn, IntPtr lParam);
