CB_GETEDITSEL
wParam = 0; /* not used, must be zero */
lParam = 0; /* not used, must be zero */
An application sends a CB_GETEDITSEL message to retrieve the starting and ending character positions of the current selection in the edit control of a combo box.
This message has no parameters.
The return value is a 32-bit value that contains the starting position in the low-order word and the position of the first nonselected character after the end of the selection in the high-order word.
CB_SETEDITSEL