ValidateRect
The ValidateRect
function validates the client area within a rectangle by removing the rectangle
from the update region of the specified window.
BOOL ValidateRect(
|
HWND hWnd, |
// handle of window
|
|
CONST RECT *lpRect |
// address of
validation rectangle coordinates |
|
); |
|
Parameters
hWnd
Identifies
the window whose update region is to be modified. If this parameter is NULL,
Windows invalidates and redraws all windows and sends the WM_ERASEBKGND and
WM_NCPAINT messages to the window procedure before the function returns.
lpRect
Points to a RECT structure that contains the
client coordinates of the rectangle to be removed from the update region. If
this parameter is NULL, the entire client area is removed.
Return Values
If the
function succeeds, the return value is nonzero.
If the
function fails, the return value is zero.
Remarks
The BeginPaint
function automatically validates the entire client area. Neither the ValidateRect
nor ValidateRgn function should be called if a portion of the update
region must be validated before the next WM_PAINT message is generated.
Windows
continues to generate WM_PAINT messages until the current update region is
validated.
See Also