Thank you for sharing the details. As I've explained in my previous mail, the problem with the groups directly from RadPivotGrid is that they are of type GroupNode (one of our internal classes), while GetAggregateValues is checking collections of other types. We'll consider improvements in this area, but meanwhile you can use the groups directly from IPivotResults:
AggregateValue aValue = results.GetAggregateResult(0, results.Root.RowGroup.Groups, results.Root.ColumnGroup.Groups);
Each Group has Groups collection of its subitems, so you will have to iterate all of them in case you want to generate the export on your own. Another tricky part is to check if row/column is collapsed or expanded - RadPivotGrid has IsRowCollapsed and IsColumnCollapsed methods, which have parameter of type IGroup, but you have to get the group from RadPivotGrid's RowGroups / ColumnGroups collection. If you try to use IsRowCollapsed method with group from IPivotResults, the method will always return false.
Hope this helps. Feel free to contact us in case you have any problems or concerns.
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