PdfRpt.DataSources.CrosstabDataSource.insertMissingTopFields C# (CSharp) Method

        private void insertMissingTopFields(List<CellData> firstRowsDataItems, int topFieldsIndex, int insertIndex)
        {
            for (var i = topFieldsIndex; i < _topFields.Count; i++)
            {
                var item = firstRowsDataItems.FirstOrDefault(x => x.PropertyName == this._topFields[i]);
                if (item == null)
                {
                    firstRowsDataItems.Insert(insertIndex,
                        new CellData
                        {
                            PropertyName = _topFields[i],
                            PropertyValue = string.Empty,
                            PropertyIndex = _index++
                        });
                }
                insertIndex++;
            }
        }