[C1Description("Group.SortExpression", "The sort expression. If empty, the group is sorted by the GroupBy value. But if specified, this is used for sorting instead. Note that aggregate functions (scoped to the group) can be used in this expression.")]
public string SortExpression { get; set; }

<C1Description("Group.SortExpression", "The sort expression. If empty, the group is sorted by the GroupBy value. But if specified, this is used for sorting instead. Note that aggregate functions (scoped to the group) can be used in this expression.")>
Public Property SortExpression As String