CB_GETCURSEL
wParam = 0; /* not used, must be zero */
lParam = 0L; /* not used, must be zero */An application sends a CB_GETCURSEL message to retrieve the index of the currently selected item, if any, in the list box of a combo box.
This message has no parameters.
The return value is the zero-based index of the currently selected item, or it is CB_ERR if no item is selected.
This example retrieves the index of the currently selected string in the list box of a combo box and then retrieves that string:
char szBuf[20];
DWORD dwIndex;
dwIndex = SendDlgItemMessage(hdlg, ID_MYCOMBOBOX, CB_GETCURSEL, 0, 0);
if (dwIndex != CB_ERR)
SendDlgItemMessage(hdlg, ID_MYCOMBOBOX,
CB_GETLBTEXT, (WPARAM) dwIndex, (LPARAM) ((LPCSTR) szBuf));