How to manipulate or iterate PivotGrid cells in server-side?

public Dictionary<string, object> InitializeGrid(string action, string gridLayout, bool enablePivotFieldList, object customObject)
        {
            //Other codes here.
            OlapDataManager dataManager = new OlapDataManager(connectionString);     dataManager.SetCurrentReport(OLAPUTILS.Utils.DeserializeOlapReport(olapReport));
            var InilizeJsonData = new OlapClient().GetJsonData(action, dataManager, pivotGridlayout);
            var PivotGridCell = new PivotCellDescriptor();
            if (dataManager.PivotEngine != null)
                pivotGridCell = dataManager.PivotEngine.TableColumns[0].Cells[0];//Here PivotGrid cells can be manipulated/iterated. 
            return InilizeJsonData;           
        }

Public Function InitializeGrid(ByVal action As String, ByVal gridLayout As String, ByVal enablePivotFieldList As Boolean, ByVal customObject As Object) As Dictionary(Of String, Object)
 'Other codes here.
 Dim dataManager As OlapDataManager = New OlapDataManager(connectionString)
 dataManager.SetCurrentReport(OLAPUTILS.Utils.DeserializeOlapReport(olapReport))
 Dim InilizeJsonData = New OlapClient().GetJsonData(action, dataManager, pivotGridlayout)
 Dim PivotGridCell = New PivotCellDescriptor()
 If dataManager.PivotEngine IsNot Nothing Then
 pivotGridCell = dataManager.PivotEngine.TableColumns(0).Cells(0) 'Here PivotGrid cells can be manipulated/iterated.
 If
 Return InilizeJsonData
End Function