| HRGN CreateRectRgn(nLeftRect, nTopRect, nRightRect, nBottomRect) | |||||
| int nLeftRect; | /* x-coordinate upper-left corner of region | */ | |||
| int nTopRect; | /* y-coordinate upper-left corner of region | */ | |||
| int nRightRect; | /* x-coordinate lower-right corner of region | */ | |||
| int nBottomRect; | /* y-coordinate lower-right corner of region | */ | |||
The CreateRectRgn function creates a rectangular region.
nLeftRect
Specifies the logical x-coordinate of the upper-left corner of the region.
nTopRect
Specifies the logical y-coordinate of the upper-left corner of the region.
nRightRect
Specifies the logical x-coordinate of the lower-right corner of the region.
nBottomRect
Specifies the logical y-coordinate of the lower-right corner of the region.
The return value is the handle of a rectangular region if the function is successful. Otherwise, it is NULL.
The size of a region is limited to 32,767 by 32,767 logical units or 64K of memory, whichever is smaller.
When it has finished using a region created by CreateRectRgn, an application should remove the region by using the DeleteObject function.
The following example uses the CreateRectRgn function to create a rectangular region, selects the region into a device context, and then uses the PaintRgn function to display the region:
HDC hdc;
HRGN hrgn;
hrgn = CreateRectRgn(10, 10, 110, 110);
SelectObject(hdc, hrgn);
PaintRgn(hdc, hrgn);CreateRectRgnIndirect, CreateRoundRectRgn, DeleteObject, PaintRgn