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when converting excel to data-table using OpenXML replaces first null column with second column which contains data in c#

excel(XLSM) file starts with first column empty and second column with values and so on it replaces the empty column with immediate column available
XLSM FILE :Before uploading
XLSM FILE:After uploading xlsm shifts to immediate null column
how to find the range or total column without shifting
i.e:when i count column it has to display as 3(A2,B2,C2)
but it gives me total column when converting
below is the code:
private void Get_XLSM_Data(ref DataTable dt)
{
string strPath = Path.GetExtension(this.FilePath);
if (strPath != null && strPath.ToUpper() == ".XLSM")
{
using (SpreadsheetDocument spreadSheetDocument =
SpreadsheetDocument.Open(this.FilePath, true))
{
IEnumerable<Sheet> sheets = spreadSheetDocument.WorkbookPart.Workbook
.GetFirstChild<Sheets>().Elements<Sheet>();
string relationshipId = sheets.First().Id.Value;
WorksheetPart worksheetPart = (WorksheetPart)spreadSheetDocument
.WorkbookPart.GetPartById(relationshipId);
Worksheet workSheet = worksheetPart.Worksheet;
var dimensionReference = workSheet.SheetDimension.Reference;
var cellTablePart = workSheet.WorksheetPart.SingleCellTablePart;
SheetData sheetData = workSheet.GetFirstChild<SheetData>();
IEnumerable<Column> columnsDescendants = sheetData.Descendants<Column>();
IEnumerable<Row> rows = sheetData.Descendants<Row>();
var sheetIdValue = sheets.First().SheetId.Value;
// ReSharper disable once PossibleNullReferenceException
var column = workSheet.GetFirstChild<SheetData>().ChildElements.FirstOrDefault().ChildElements.Count();
if (dt.TableName == "specific table ")
{
dt.Columns.Clear();
for (int col = 1; col <= column; col++)
{
string colName = "Column" + (col);
dt.Columns.Add(colName);
}
//// START: To add Headers (First row) in data table
string[] rowData = new string[dt.Columns.Count];
int colIndex = 0;
foreach (Cell cell in rows.ElementAt(0))
{
rowData[colIndex] = GetCellValue(spreadSheetDocument, cell); colIndex++;
}
dt.Rows.Add(rowData);
//// END: To add Headers (First row) in data table
}
try
{
for (int i = 1; i < rows.Count(); i++)
{
string[] rowData = new string[dt.Columns.Count];
int col = 0;
foreach (Cell cell in rows.ElementAt(i))
{
rowData[col] = GetCellValue(spreadSheetDocument, cell); col++;
}
dt.Rows.Add(rowData);
}
}
}
}
}
public static string GetCellValue(SpreadsheetDocument document, Cell cell)
{
SharedStringTablePart stringTablePart = document.WorkbookPart.SharedStringTablePart;
if (cell != null)
{
string cellValue = cell.CellValue != null ? cell.CellValue.InnerXml : String.Empty;
if (cell.DataType != null && cell.DataType.Value == CellValues.SharedString)
{
cellValue = stringTablePart.SharedStringTable.ChildElements[Int32.Parse(cellValue)].InnerText;
}
else
{
if(!string.IsNullOrEmpty(cellValue))
{
//return Convert.ToString(cellValue, CultureInfo.InvariantCulture);
return double.Parse(cellValue, CultureInfo.InvariantCulture).ToString();
}
return cellValue;
}
return cellValue;
}
return String.Empty;
}

Row row = worksheetPart.Worksheet.GetFirstChild<SheetData>().Elements<Row>().FirstOrDefault();
var totalnumberOfColumns = 0;
if (row != null)
{
var spans = row.Spans != null ? row.Spans.InnerText : "";
if (spans != String.Empty)
{
//spans.Split(':')[1];
string[] columns = spans.Split(':');
startcolumnInuse = int.Parse(columns[0]);
endColumnInUse = int.Parse(columns[1]);
totalnumberOfColumns = int.Parse(columns[1]);
}
}
Below is the screen shot to find the maximum column present through span with above code i have shared
Here i have used different excel file(XLSM)

Below is the screen shot to find the maximum column present through span
with above code i have shared
Here i have used different excel file(XLSM)

OpenXml SAX Approach

I am attempting to use the SAX approach to process large excel files. In my scenario, the user will map some columns from the spreadsheet, and we will get the data from each row based on the position of the cell and the value of the cell.
The process is working, but I was hoping for it to take less time. Does it appear that I am doing anything wrong?
private string GetCellValue(Cell c, WorkbookPart workbookPart)
{
if (c.DataType != null && c.DataType == CellValues.SharedString)
{
return workbookPart.SharedStringTablePart.SharedStringTable.Elements<SharedStringItem>()
.ElementAt(int.Parse(c.CellValue.InnerText)).Text.Text;
}
return c.CellValue != null ? c.CellValue.InnerText : string.Empty;
}
private void ProcessDocument()
{
using (var spreadsheetDocument = SpreadsheetDocument.Open(model.FileName, false))
{
WorkbookPart workbookPart = spreadsheetDocument.WorkbookPart;
WorksheetPart worksheetPart = workbookPart.WorksheetParts.First();
var reader = OpenXmlReader.Create(worksheetPart);
while (reader.Read())
{
if (reader.ElementType != typeof(Row))
{
continue;
}
rowCount++;
reader.ReadFirstChild();
var values = new ParcelValueImportValues();
do
{
if (reader.ElementType != typeof(Cell) || rowCount <= 1)
{
continue;
}
var c = (Cell)reader.LoadCurrentElement();
var location = GetCellLocation(c.CellReference);
var cellValue = GetCellValue(c, workbookPart);
if (location.Equals(hist.AssessmentRatio))
{
values.AssessmentRatio = cellValue;
}
else if (location.Equals(hist.AvImprovements))
{
values.AvImprovements = cellValue;
}
else if (location.Equals(hist.AvLand))
{
values.AvLand = cellValue;
}
else if (location.Equals(hist.FmvLand))
{
values.FmvLand = cellValue;
}
else if (location.Equals(hist.FmvImprovements))
{
values.FmvImprovements = cellValue;
}
else if (location.Equals(hist.ParcelNumber))
{
values.ParcelNumber = cellValue;
}
} while (reader.ReadNextSibling());
}
}
}

OpenXML Only reading 4 columns

I have the following piece of code in a much larger OpenXML Excel reader. This reader grabs the information assigns to a dataset and then is displayed in a datagridview:
public static DataTable ExtractExcelSheetValuesToDataTable(string xlsxFilePath, string sheetName, int startingRow) {
DataTable dt = new DataTable();
using (SpreadsheetDocument myWorkbook = SpreadsheetDocument.Open(xlsxFilePath, true)) {
//Access the main Workbook part, which contains data
WorkbookPart workbookPart = myWorkbook.WorkbookPart;
WorksheetPart worksheetPart = null;
if (!string.IsNullOrEmpty(sheetName)) {
Sheet ss = workbookPart.Workbook.Descendants<Sheet>().Where(s => s.Name == sheetName).SingleOrDefault<Sheet>();
worksheetPart = (WorksheetPart)workbookPart.GetPartById(ss.Id);
} else {
worksheetPart = workbookPart.WorksheetParts.FirstOrDefault();
}
SharedStringTablePart stringTablePart = workbookPart.SharedStringTablePart;
if (worksheetPart != null) {
Row lastRow = worksheetPart.Worksheet.Descendants<Row>().LastOrDefault();
#region ColumnCreation
//Returns the columns - come back to this later - may be able to modify this to have
//A checkbox "Column names in first row"
Row firstRow = worksheetPart.Worksheet.Descendants<Row>().FirstOrDefault();
int columnInt = 0;
//if (firstRow != null)
//{
foreach (Cell c in firstRow.ChildElements)
{
string value = GetValue(c, stringTablePart);
dt.Columns.Add(columnInt + ": " + value);
columnInt++;
}
//}
#endregion
#region Create Rows
//if (lastRow != null)
//{
//lastRow.RowIndex;
for (int i = startingRow; i <= 150000; i++)
{
DataRow dr = dt.NewRow();
bool empty = true;
Row row = worksheetPart.Worksheet.Descendants<Row>().Where(r => i == r.RowIndex).FirstOrDefault();
int j = 0;
if (row != null)
{
foreach (Cell c in row.ChildElements)
{
//Get cell value
string value = GetValue(c, stringTablePart);
if (!string.IsNullOrEmpty(value) && value != "")
empty = false;
dr[j] = value;
j++;
if (j == dt.Columns.Count)
break;
}
if (empty)
break;
dt.Rows.Add(dr);
}
}
}
#endregion
}
// }
return dt;
}
public static string GetValue(Cell cell, SharedStringTablePart stringTablePart) {
if (cell.ChildElements.Count == 0) return null;
//get cell value
string value = cell.ElementAt(0).InnerText;//CellValue.InnerText;
//Look up real value from shared string table
if ((cell.DataType != null) && (cell.DataType == CellValues.SharedString))
value = stringTablePart.SharedStringTable.ChildElements[Int32.Parse(value)].InnerText;
return value;
}
public void GetSheetInfo(string fileName)
{
Sheets theSheets = null;
// Open file as read-only.
using (SpreadsheetDocument mySpreadsheet = SpreadsheetDocument.Open(fileName, false))
{
S sheets = mySpreadsheet.WorkbookPart.Workbook.Sheets;
WorkbookPart wbPart = mySpreadsheet.WorkbookPart;
theSheets = wbPart.Workbook.Sheets;
foreach (Sheet item in theSheets)
{
cmbSheetSelect.Items.Add(item.Name);
}
}
}
This has worked for basic spreadsheets but as I try to read more advanced ones I get a problem or two.
Firstly, I have a worksheet that has 5 columns:see here
However when I run my program it only returns the first 4 columns and not column E and all its data.
My second question would is it possible using that code (or a variation of it) to be able to specify the line I want the program to read as the datagridview column heading?

In case anyone needs this I found that changing:
Row firstRow = worksheetPart.Worksheet.Descendants<Row>().FirstOrDefault();
To
Row firstRow = worksheetPart.Worksheet.Descendants<Row>().ElementAtOrDefault(columnIndex)
Worked. With columnIndex being a variable I can change based on the sheet selected.

How can I deep clone row in .xlsx file using openXML?

I have template.xlsx file which I must modify by adding a few copies of one row in specific index. When I try use clone method for this operation I add a row but each row modify each other. I need to create deep clone of opemxml row object but when I try this I have an error that openxml row object are not serialized. How can I deep clone row in .xlsx file using openXML with serialization or if there is another way to deep clone openxml row object?

You can deep clone using .CloneNode(true) on an OpenXmlElement
So if you want to duplicate a row inside a table it will look like
// suppose table an OpenXml Table and row the row you want to clone
table.Append(row.CloneNode(true));
edit :
to insert it before a specific row
// suppose r is the row you want to insert it before
r.InsertBeforeSelf(row.CloneNode(true));

In my case, I needed to copy several rows at the end of the sheet.
I literally needed to clone a specific range of rows, i.e. values, styles and formulas, merged cells. After spending many hours on the problem of copy and paste several rows, I finally found a solution. I was able to copy rows 18 to 26 and paste them from row 27.
Example below:
Below is the code:
public static void CopyRowRange(SpreadsheetDocument document, string sheetName,
int srcRowFrom, int srcRowTo, int destRowFrom)
{
WorkbookPart workbookPart = document.WorkbookPart;
if (srcRowTo < srcRowFrom || destRowFrom < srcRowFrom) return;
int destRowFromBase = destRowFrom;
WorksheetPart worksheetPart = GetWorksheetPartByName(document, sheetName);
SheetData sheetData = worksheetPart.Worksheet.GetFirstChild<SheetData>();
IList<Cell> cells = sheetData.Descendants<Cell>().Where(c =>
GetRowIndex(c.CellReference) >= srcRowFrom &&
GetRowIndex(c.CellReference) <= srcRowTo).ToList<Cell>();
if (cells.Count() == 0) return;
int copiedRowCount = srcRowTo - srcRowFrom + 1;
MoveRowIndex(document, sheetName, destRowFrom - 1, srcRowTo, srcRowFrom);
IDictionary<int, IList<Cell>> clonedCells = null;
IList<Cell> formulaCells = new List<Cell>();
IList<Row> cloneRelatedRows = new List<Row>();
destRowFrom = destRowFromBase;
int changedRowsCount = destRowFrom - srcRowFrom;
formulaCells.Clear();
clonedCells = new Dictionary<int, IList<Cell>>();
foreach (Cell cell in cells)
{
Cell newCell = (Cell)cell.CloneNode(true);
int index = Convert.ToInt32(GetRowIndex(cell.CellReference));
int rowIndex = index - changedRowsCount;
newCell.CellReference = GetColumnName(cell.CellReference) + rowIndex.ToString();
IList<Cell> rowCells = null;
if (clonedCells.ContainsKey(rowIndex))
rowCells = clonedCells[rowIndex];
else
{
rowCells = new List<Cell>();
clonedCells.Add(rowIndex, rowCells);
}
rowCells.Add(newCell);
if (newCell.CellFormula != null && newCell.CellFormula.Text.Length > 0)
{
formulaCells.Add(newCell);
}
}
foreach (int rowIndex in clonedCells.Keys)
{
Row row = sheetData.Elements<Row>().Where(r => r.RowIndex == rowIndex).FirstOrDefault();
if (row == null)
{
row = new Row() { RowIndex = (uint)rowIndex };
Row refRow = sheetData.Elements<Row>().Where(r => r.RowIndex > rowIndex).OrderBy(r => r.RowIndex).FirstOrDefault();
if (refRow == null)
sheetData.AppendChild<Row>(row);
else
sheetData.InsertBefore<Row>(row, refRow);
}
row.Append(clonedCells[rowIndex].ToArray());
cloneRelatedRows.Add(row);
}
ChangeFormulaRowNumber(worksheetPart.Worksheet, formulaCells, changedRowsCount);
foreach (Row row in cloneRelatedRows)
{
IList<Cell> cs = row.Elements<Cell>().OrderBy(c => c.CellReference.Value).ToList<Cell>();
row.RemoveAllChildren();
row.Append(cs.ToArray());
}
MergeCells mcells = worksheetPart.Worksheet.GetFirstChild<MergeCells>();
if (mcells != null)
{
IList<MergeCell> newMergeCells = new List<MergeCell>();
IEnumerable<MergeCell> clonedMergeCells = mcells.Elements<MergeCell>().
Where(m => MergeCellInRange(m, srcRowFrom, srcRowTo)).ToList<MergeCell>();
foreach (MergeCell cmCell in clonedMergeCells)
{
MergeCell newMergeCell = CreateChangedRowMergeCell(worksheetPart.Worksheet, cmCell, changedRowsCount);
newMergeCells.Add(newMergeCell);
}
uint count = mcells.Count.Value;
mcells.Count = new UInt32Value(count + (uint)newMergeCells.Count);
mcells.Append(newMergeCells.ToArray());
}
}
private static WorksheetPart
GetWorksheetPartByName(SpreadsheetDocument document,
string sheetName)
{
IEnumerable<Sheet> sheets =
document.WorkbookPart.Workbook.GetFirstChild<Sheets>().
Elements<Sheet>().Where(s => s.Name == sheetName);
if (sheets.Count() == 0)
{
return null;
}
string relationshipId = sheets.First().Id.Value;
WorksheetPart worksheetPart = (WorksheetPart)
document.WorkbookPart.GetPartById(relationshipId);
return worksheetPart;
}
private static void MoveRowIndex(SpreadsheetDocument document, string sheetName, int destRowFrom, int srcRowTo, int srcRowFrom)
{
WorksheetPart worksheetPart = GetWorksheetPartByName(document, sheetName);
SheetData sheetData = worksheetPart.Worksheet.GetFirstChild<SheetData>();
uint newRowIndex;
IEnumerable<Row> rows = sheetData.Descendants<Row>().Where(r => r.RowIndex.Value >= srcRowFrom && r.RowIndex.Value <= srcRowTo);
foreach (Row row in rows)
{
newRowIndex = Convert.ToUInt32(destRowFrom + 1);
foreach (Cell cell in row.Elements<Cell>())
{
string cellReference = cell.CellReference.Value;
cell.CellReference = new StringValue(cellReference.Replace(row.RowIndex.Value.ToString(), newRowIndex.ToString()));
}
row.RowIndex = new UInt32Value(newRowIndex);
destRowFrom++;
}
}
private static void ChangeFormulaRowNumber(Worksheet worksheet, IList<Cell> formulaCells, int changedRowsCount)
{
foreach (Cell formulaCell in formulaCells)
{
Regex regex = new Regex(#"\d+");
var rowIndex = Convert.ToInt32(regex.Match(formulaCell.CellReference).Value);
Regex regex2 = new Regex("[A-Za-z]+");
var columnIndex = regex2.Match(formulaCell.CellReference).Value;
int newRowIndex = rowIndex + changedRowsCount;
Cell cell = GetCell(worksheet, columnIndex, newRowIndex);
cell.CellFormula = new CellFormula(cell.CellFormula.Text.Replace($"{rowIndex}",$"{newRowIndex}"));
}
}
private static MergeCell CreateChangedRowMergeCell(Worksheet worksheet, MergeCell cmCell, int changedRows)
{
string[] cells = cmCell.Reference.Value.Split(':', 2, StringSplitOptions.RemoveEmptyEntries);
Regex regex = new Regex(#"\d+");
var rowIndex1 = Convert.ToInt32(regex.Match(cells[0]).Value);
var rowIndex2 = Convert.ToInt32(regex.Match(cells[1]).Value);
Regex regex2 = new Regex("[A-Za-z]+");
var columnIndex1 = regex2.Match(cells[0]).Value;
var columnIndex2 = regex2.Match(cells[1]).Value;
var cell1Name = $"{columnIndex1}{rowIndex1 + changedRows}";
var cell2Name = $"{columnIndex2}{rowIndex2 + changedRows}";
CreateSpreadsheetCellIfNotExist(worksheet, cell1Name);
CreateSpreadsheetCellIfNotExist(worksheet, cell2Name);
return new MergeCell() { Reference = new StringValue(cell1Name + ":" + cell2Name) };
}
private static bool MergeCellInRange(MergeCell mergeCell, int srcRowFrom, int srcRowTo)
{
string[] cells = mergeCell.Reference.Value.Split(':', 2, StringSplitOptions.RemoveEmptyEntries);
Regex regex = new Regex(#"\d+");
var cellIndex1 = Convert.ToInt32(regex.Match(cells[0]).Value);
var cellIndex2 = Convert.ToInt32(regex.Match(cells[1]).Value);
if (srcRowFrom <= cellIndex1 && cellIndex1 <= srcRowTo &&
srcRowFrom <= cellIndex2 && cellIndex2 <= srcRowTo)
return true;
else
return false;
}
private static uint GetRowIndex(string cellName)
{
Regex regex = new Regex(#"\d+");
Match match = regex.Match(cellName);
return uint.Parse(match.Value);
}
private static string GetColumnName(string cellName)
{
Regex regex = new Regex("[A-Za-z]+");
Match match = regex.Match(cellName);
return match.Value;
}
private static void CreateSpreadsheetCellIfNotExist(Worksheet worksheet, string cellName)
{
string columnName = GetColumnName(cellName);
uint rowIndex = GetRowIndex(cellName);
IEnumerable<Row> rows = worksheet.Descendants<Row>().Where(r => r.RowIndex.Value == rowIndex);
if (rows.Count() == 0)
{
Row row = new Row() { RowIndex = new UInt32Value(rowIndex) };
Cell cell = new Cell() { CellReference = new StringValue(cellName) };
row.Append(cell);
worksheet.Descendants<SheetData>().First().Append(row);
worksheet.Save();
}
else
{
Row row = rows.First();
IEnumerable<Cell> cells = row.Elements<Cell>().Where(c => c.CellReference.Value == cellName);
if (cells.Count() == 0)
{
Cell cell = new Cell() { CellReference = new StringValue(cellName) };
row.Append(cell);
worksheet.Save();
}
}
}
private static Cell GetCell(Worksheet worksheet, string columnIndex, int newRowIndex)
{
string cellName = columnIndex + newRowIndex;
Row row = worksheet.GetFirstChild<SheetData>().Descendants<Row>().FirstOrDefault(r => r.RowIndex.Value == newRowIndex);
return row.Elements<Cell>().FirstOrDefault(c => c.CellReference.Value == cellName);
}

Problem with skipping empty cells while importing data from .xlsx file in asp.net c# application

I have a problem with reading .xlsx files in asp.net mvc2.0 application, using c#. Problem occurs when reading empty cell from .xlsx file. My code simply skips this cell and reads the next one.
For example, if the contents of .xlsx file are:
FirstName LastName Age
John 36
They will be read as:
FirstName LastName Age
John 36
Here's the code that does the reading.
private string GetValue(Cell cell, SharedStringTablePart stringTablePart)
{
if (cell.ChildElements.Count == 0)
return string.Empty;
//get cell value
string value = cell.ElementAt(0).InnerText;//CellValue.InnerText;
//Look up real value from shared string table
if ((cell.DataType != null) && (cell.DataType == CellValues.SharedString))
value = stringTablePart.SharedStringTable.ChildElements[Int32.Parse(value)].InnerText;
return value;
}
private DataTable ExtractExcelSheetValuesToDataTable(string xlsxFilePath, string sheetName)
{
DataTable dt = new DataTable();
using (SpreadsheetDocument myWorkbook = SpreadsheetDocument.Open(xlsxFilePath, true))
{
//Access the main Workbook part, which contains data
WorkbookPart workbookPart = myWorkbook.WorkbookPart;
WorksheetPart worksheetPart = null;
if (!string.IsNullOrEmpty(sheetName))
{
Sheet ss = workbookPart.Workbook.Descendants<Sheet>().Where(s => s.Name == sheetName).SingleOrDefault<Sheet>();
worksheetPart = (WorksheetPart)workbookPart.GetPartById(ss.Id);
}
else
{
worksheetPart = workbookPart.WorksheetParts.FirstOrDefault();
}
SharedStringTablePart stringTablePart = workbookPart.SharedStringTablePart;
if (worksheetPart != null)
{
Row lastRow = worksheetPart.Worksheet.Descendants<Row>().LastOrDefault();
Row firstRow = worksheetPart.Worksheet.Descendants<Row>().FirstOrDefault();
if (firstRow != null)
{
foreach (Cell c in firstRow.ChildElements)
{
string value = GetValue(c, stringTablePart);
dt.Columns.Add(value);
}
}
if (lastRow != null)
{
for (int i = 2; i <= lastRow.RowIndex; i++)
{
DataRow dr = dt.NewRow();
bool empty = true;
Row row = worksheetPart.Worksheet.Descendants<Row>().Where(r => i == r.RowIndex).FirstOrDefault();
int j = 0;
if (row != null)
{
foreach (Cell c in row.ChildElements)
{
//Get cell value
string value = GetValue(c, stringTablePart);
if (!string.IsNullOrEmpty(value) && value != "")
empty = false;
dr[j] = value;
j++;
if (j == dt.Columns.Count)
break;
}
if (empty)
break;
dt.Rows.Add(dr);
}
}
}
}
}
return dt;
}

i had same problem.
This is my workout:
int offset = GetColDiff(lastCol, cell.CellReference);
//filling empty columns
while (offset-- > 1)
dt.Rows[rowCounter][cnt++] = DBNull.Value;
//filling regular column
dt.Rows[rowCounter][cnt++] = value;
lastCol = cell.CellReference;
******************
//calculating column distance
int GetColDiff(string prev, string curr)
{
int i=0;
int index1 = 0;
int index2 = 0;
while (prev!="0" && prev.Length>i && Char.IsLetter(prev[i]))//prev=="0"-startingcondition
{
index1 += ('Z' - 'A' + 1) * index1 + (prev[i] - 'A');
i++;
}
i = 0;
while (curr.Length>i && char.IsLetter(curr[i]))
{
index2 += ('Z' - 'A'+ 1) * index2 + (curr[i] - 'A');
i++;
}
return index2 - index1;
}

My solution to this problem isn't quite as elegant as some might use.
First, I map the columns to a char (A, B, C, D, etc), so I can know that FirstName = A, LastName = B, and Age = C.
Next, I look through the dataCells to see if there is a cell that has the Age reference. If there is a Age cell referenced, I will check the cell's DataType.
ex: dataCells.Where(x => x.CellReference.Value.Contains(cellIndex)).First().DataType == CellValues.SharedString)
In this case, cellIndex would = 'C'.
If the previous linq query is true, then you'll go to the sharedString table and find the value for the age by CellReference.
var age = sharedStrings.ChildElements[int.Parse(dataCells.Where(x => x.CellReference.Value.Contains(cellIndex)).FirstOrDefault().InnerText)].InnerText;
Your problem with accidentally setting the LastName (Column B) to whatever the Age (Column C) should be avoided if you work off of cell reference for each DataRow.
Side note: One thing I just ran into is that blank cells in Excel are stored two different ways. Sometimes there's a reference to a SharedStringTable index (cell.DataType = "s" and cell.InnerText = "37"), and sometimes the cell is just empty (cell.DataType = null and cell.InnerText = "").