GetWindowRgn 函数

The GetWindowRgn function obtains a copy of the window region of a window. The window region of a window is set by calling the SetWindowRgn function. The window region determines the area within the window where the system permits drawing. The system does not display any portion of a window that lies outside of the window region

定义

int GetWindowRgn(HWND hWnd, HRGN hRgn);

参数

hWnd

Handle to the window whose window region is to be obtained.

hRgn

Handle to the region which will be modified to represent the window region.

返回值

The return value specifies the type of the region that the function obtains. It can be one of the following values.

NULLREGION - The region is empty.

SIMPLEREGION - The region is a single rectangle.

COMPLEXREGION - The region is more than one rectangle.

ERROR - The specified window does not have a region, or an error occurred while attempting to return the region.

说明

The coordinates of a window's window region are relative to the upper-left corner of the window, not the client area of the window.

To set the window region of a window, call the SetWindowRgn function.

系统要求

Windows NT/2000/XP: Included in Windows NT 3.51 and later.

Windows 95/98/Me: Included in Windows 95 and later.

Header: Declared in Winuser.h; include Windows.h.

Library: Use User32.lib.