The GetTopWindow function examines the Z order of the child windows associated with the specified parent window and retrieves a handle to the child window at the top of the Z order.
HWND GetTopWindow(
HWND hWnd // handle to parent window
);
If the function succeeds, the return value is a handle to the child window at the top of the Z order. If the specified window has no child windows, the return value is NULL. To get extended error information, use the GetLastError function.
Windows NT: Requires version 3.1 or later.
Windows: Requires Windows 95 or later.
Windows CE: Unsupported.
Header: Declared in winuser.h.
Import Library: Use user32.lib.
Windows Overview, Window Functions, GetNextWindow, GetWindow