The RadPivotGrid does not provide way for accessing the filter expressions as in the RadGrid, because if it's more complex way of internal filtering. The closest thing is to use IQueryable
as DataSource and use it's Expression.
Another option is to use the FilterWindow property of the PivotGrid to get the filtering window, and then the SetBox property of this window to access the RadListBox that holds filter values that can be checked.
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