Mike,

I think you can use middle mouse button (scroll wheel) to do that.

* Grid's MouseWhell
LPARAMETERS nDirection, nShift, nXCoord, nYCoord
DECLARE SHORT  GetKeyState IN WIN32API INTEGER
#define VK_LBUTTON        0x01
#define VK_RBUTTON        0x02
#define VK_MBUTTON        0x04
IF GetKeyState( VK_MBUTTON ) < 0 ;
		AND GetKeyState( VK_LBUTTON ) >= 0 ;
		AND GetKeyState( VK_RBUTTON ) >= 0 
  * The middle mouse button is down
	WAIT WINDOW PROGRAM() 
ENDIF	

>Hi Sergey,
>
>I was trying to provide the user with a way to change the fontsize in the grid by using the mousewheel to enlarge or reduce the size. I wanted to use Shift + wheel so as to preserve the default behaviour of the mousewheel in a grid (ie to scroll the grid's contents).
>
>I've tried successfully to do what I need if I don't try to trap the Shift key. The grid's contents grow or shrink when I spin the mousewheel. It just doesn't want to work if I test for nShift :(
>
>