CB_GETDROPPEDCONTROLRECT
wParam = 0; /* not used, must be zero */
lParam = (LPARAM) (RECT FAR*) lprc; /* address of RECT structure */
An application sends a CB_GETDROPPEDCONTROLRECT message to retrieve the screen coordinates of the visible (dropped-down) list box of a combo box.
lprc
Value of lParam. Points to the RECT structure that is to receive the coordinates. The RECT structure has the following form:
typedef struct tagRECT { /* rc */
int left;
int top;
int right;
int bottom;
} RECT;
The return value is always CB_OKAY.
This example retrieves the bounding rectangle of the list box of a combo box:
RECT
rcl; SendDlgItemMessage(hdlg, ID_MYCOMBOBOX, CB_GETDROPPEDCONTROLRECT, 0, (DWORD) ((LPRECT) &rcl));