REFERENCE GUIDE

GetTickCountReturn valueCommentsThe return value specifies the number of milliseconds that have elapsedsince the system was started.The count is accurate within ±55 milliseconds.GetTopWindowSyntaxHWND GetTopWindow(hWnd)function GetTopWindow(Wnd: HWnd): HWnd;This function searches for a handle to the top-level child window thatbelongs to the parent window associated with the h Wnd parameter. If thewindow has no children, this function returns NULL:Parameters h Wnd HWND Identifies the parent window.Return valueThe return value identifies a handle to the top-level child window in aparent window's linked list of child windows. If no child windows exist, itis NULL.IGetUpdateRectSyntaxParametersBOOL GetUpdateRect(h Wnd, IpRect, bErase)function GetUpdateRect(Wnd: HWnd; var Rect: TRect; Erase: Book): Bool;This function retrieves the coordinates of the smallest rectangle thatcompletely encloses the update region of the given window. If thewindow was created with the CS_OWNDC style and the mapping modeis not MM_ TEXT, the GetUpdateRect function gives the rectangle inlogical coordinates. Otherwise, GetUpdateRect gives the rectangle inclient coordinates. If there is no update region, GetUpdateRect makes therectangle empty (sets all coordinates to zero).The bErase parameter specifies whether GetUpdateRect should erase thebackground of the update region. If bErase is TRUE and the update regionis not empty, the background is erased. To erase the background,GetUpdateRect sends a WM_ERASEBKGND message to the givenwindow.h WndIpRectHWND Identifies the window whose update region is to beretrieved.LPRECT Points to the RECT data structure that is to receivethe client coordinates of the enclosing rectangle.Chapter 4, Functions directory357