protected void ASPxPivotGrid2_GroupFilterChanged(object sender, PivotGroupEventArgs e)
    {
        var    fi     = FilterInfo.GetFilterInfo(e.Group, PivotFilterType.Included);
        string result = FilterInfo.WriterHierachyToString(fi, "");

        ASPxPivotGrid2.JSProperties.Add("cpFilter", result);
    }