public int Add(CDisc cd, TreeNodeCollection tnc, int index)
 {
     Functions.FillTreeView(cd.Folders, tnc);
     List.Insert(index, cd);
     return(index);
 }
 public int Add(CDisc cd, TreeNodeCollection tnc)
 {
     Functions.FillTreeView(cd.Folders, tnc);
     return(List.Add(cd));
 }