public override int GetHashCode()
        {
            var hash = "ConnectionString" + (ConnectionString ?? String.Empty) + "GroupName" + (GroupName ?? String.Empty);

            if (ConnectionStrings != null && ConnectionStrings.Count != 0)
            {
                ConnectionStrings.ForEach(
                    el => hash += el == null ? String.Empty
                                                : ("el.Name" + el.Name + "el.ConnectionString" + el.ConnectionString + "el.IsODBC" + el.IsODBC.ToString()));
            }

            return(hash.GetHashCode());
        }