WriteRowsLoop.cs

foreach (Row currentRow in rows)
{
    //write the row start element with the attributes added above 
    _writer.WriteStartElement(currentRow);

    foreach (OpenXmlElement currentCell in currentRow.ChildElements)
    {
        var cell = (Cell)currentCell;

        //write the start of the cell element with the type and cell reference attributes 
        _writer.WriteStartElement(cell);

        //write the cell value 
        _writer.WriteElement(cell.CellValue);

        //write the cell end element 
        _writer.WriteEndElement();
    }

    //write the row end element 
    _writer.WriteEndElement();
}