SetWindowPos 参数及用法（API）

BOOL SetWindowPos( const CWnd* pWndInsertAfter, int x, int y, int cx, int cy, UINT nFlags );

Nonzero if the function is successful; otherwise 0.

CWnd object that will precede this CWnd object in the Z-order. This parameter can be a pointer to a CWnd or a Pointer to one of the following values:

• wndBottomPlaces the window at the bottom of the Z-order. If this CWnd is a topmost window, the window loses its topmost status; the system places the window at the bottom of all other windows.
• wndTopPlaces the window at the top of the Z-order.
• wndTopMostPlaces the window above all nontopmost windows. The window maintains its topmost position even when it is deactivated.
• wndNoTopMostRepositions the window to the top of all nontopmost windows (that is, behind all topmost windows). This flag has no effect if the window is already a nontopmost window.

• SWP_DRAWFRAMEDraws a frame (defined when the window was created) around the window.
• SWP_FRAMECHANGEDSends a WM_NCCALCSIZE message to the window, even if the window's size is not being changed. If this flag is not specified, WM_NCCALCSIZE is sent only when the window's size is being changed.
• SWP_HIDEWINDOWHides the window.
• SWP_NOACTIVATEDoes not activate the window. If this flag is not set, the window is activated and moved to the top of either the topmost or the nontopmost group (depending on the setting of the pWndInsertAfter parameter).
• SWP_NOCOPYBITSDiscards the entire contents of the client area. If this flag is not specified, the valid contents of the client area are saved and copied back into the client area after the window is sized or repositioned.
• SWP_NOMOVERetains current position (ignores the x and y parameters).
• SWP_NOOWNERZORDERDoes not change the owner window’s position in the Z-order.
• SWP_NOREDRAWDoes not redraw changes. If this flag is set, no repainting of any kind occurs. This applies to the client area, the nonclient area (including the title and scroll bars), and any part of the parent window uncovered as a result of the moved window. When this flag is set, the application must explicitly invalidate or redraw any parts of the window and parent window that must be redrawn.
• SWP_NOREPOSITIONSame as SWP_NOOWNERZORDER.
• SWP_NOSENDCHANGINGPrevents the window from receiving the WM_WINDOWPOSCHANGING message.
• SWP_NOSIZERetains current size (ignores the cx and cy parameters).
• SWP_NOZORDERRetains current ordering (ignores pWndInsertAfter).
• SWP_SHOWWINDOWDisplays the window.