int SetCurSel( int nSelect );
nSelect
Specifies the zero-based index of the string to be selected. If nSelect is -1, the list box is set to have no selection.
Selects a string and scrolls it into view, if necessary. When the new string is selected, the list box removes the highlight from the previously selected string.
Use this member function only with single-selection list boxes. It cannot be used to set or remove a selection in a multiple-selection list box.
LB_ERR if an error occurs.
LB_SETCURSEL, CListBox::GetCurSel