Insert text into a cell in a spreadsheet document

This topic shows how to use the classes in the Open XML SDK for Office to insert text into a cell in a new worksheet in a spreadsheet document programmatically.

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Basic structure of a spreadsheetML document

The basic document structure of a SpreadsheetML document consists of the Sheets and Sheet elements, which reference the worksheets in the workbook. A separate XML file is created for each worksheet. For example, the SpreadsheetML for a Workbook that has two worksheets name MySheet1 and MySheet2 is located in the Workbook.xml file and is shown in the following code example.

    <?xml version="1.0" encoding="UTF-8" standalone="yes" ?> 
    <workbook xmlns=https://schemas.openxmlformats.org/spreadsheetml/2006/main xmlns:r="https://schemas.openxmlformats.org/officeDocument/2006/relationships">
        <sheets>
            <sheet name="MySheet1" sheetId="1" r:id="rId1" /> 
            <sheet name="MySheet2" sheetId="2" r:id="rId2" /> 
        </sheets>
    </workbook>

The worksheet XML files contain one or more block level elements such as sheetData represents the cell table and contains one or more Row elements. A row contains one or more Cell elements. Each cell contains a CellValue element that represents the value of the cell. For example, the SpreadsheetML for the first worksheet in a workbook, that only has the value 100 in cell A1, is located in the Sheet1.xml file and is shown in the following code example.

    <?xml version="1.0" encoding="UTF-8" ?> 
    <worksheet xmlns="http://schemas.openxmlformats.org/spreadsheetml/2006/main">
        <sheetData>
            <row r="1">
                <c r="A1">
                    <v>100</v> 
                </c>
            </row>
        </sheetData>
    </worksheet>

Using the Open XML SDK, you can create document structure and content that uses strongly-typed classes that correspond to SpreadsheetML elements. You can find these classes in the DocumentFormat.OpenXML.Spreadsheet namespace. The following table lists the class names of the classes that correspond to the workbook, sheets, sheet, worksheet, and sheetData elements.

SpreadsheetML Element	Open XML SDK Class	Description
workbook	DocumentFormat.OpenXML.Spreadsheet.Workbook	The root element for the main document part.
sheets	DocumentFormat.OpenXML.Spreadsheet.Sheets	The container for the block level structures such as sheet, fileVersion, and others specified in the ISO/IEC 29500 specification.
sheet	DocumentFormat.OpenXml.Spreadsheet.Sheet	A sheet that points to a sheet definition file.
worksheet	DocumentFormat.OpenXML.Spreadsheet. Worksheet	A sheet definition file that contains the sheet data.
sheetData	DocumentFormat.OpenXML.Spreadsheet.SheetData	The cell table, grouped together by rows.
row	DocumentFormat.OpenXml.Spreadsheet.Row	A row in the cell table.
c	DocumentFormat.OpenXml.Spreadsheet.Cell	A cell in a row.
v	DocumentFormat.OpenXml.Spreadsheet.CellValue	The value of a cell.

How the Sample Code Works

After opening the SpreadsheetDocument document for editing, the code inserts a blank Worksheet object into a SpreadsheetDocument document package. Then, inserts a new Cell object into the new worksheet and inserts the specified text into that cell.

C#

// Given a document name and text, 
// inserts a new work sheet and writes the text to cell "A1" of the new worksheet.
static void InsertText(string docName, string text)
{
    // Open the document for editing.
    using (SpreadsheetDocument spreadSheet = SpreadsheetDocument.Open(docName, true))
    {
        WorkbookPart workbookPart = spreadSheet.WorkbookPart ?? spreadSheet.AddWorkbookPart();

        // Get the SharedStringTablePart. If it does not exist, create a new one.
        SharedStringTablePart shareStringPart;
        if (workbookPart.GetPartsOfType<SharedStringTablePart>().Count() > 0)
        {
            shareStringPart = workbookPart.GetPartsOfType<SharedStringTablePart>().First();
        }
        else
        {
            shareStringPart = workbookPart.AddNewPart<SharedStringTablePart>();
        }

        // Insert the text into the SharedStringTablePart.
        int index = InsertSharedStringItem(text, shareStringPart);

        // Insert a new worksheet.
        WorksheetPart worksheetPart = InsertWorksheet(workbookPart);

        // Insert cell A1 into the new worksheet.
        Cell cell = InsertCellInWorksheet("A", 1, worksheetPart);

        // Set the value of cell A1.
        cell.CellValue = new CellValue(index.ToString());
        cell.DataType = new EnumValue<CellValues>(CellValues.SharedString);

        // Save the new worksheet.
        worksheetPart.Worksheet.Save();
    }
}

Visual Basic

' Given a document name and text, 
' inserts a new worksheet and writes the text to cell "A1" of the new worksheet.
Public Function InsertText(ByVal docName As String, ByVal text As String)
    ' Open the document for editing.
    Dim spreadSheet As SpreadsheetDocument = SpreadsheetDocument.Open(docName, True)

    Using (spreadSheet)
        ' Get the SharedStringTablePart. If it does not exist, create a new one.
        Dim shareStringPart As SharedStringTablePart

        If (spreadSheet.WorkbookPart.GetPartsOfType(Of SharedStringTablePart).Count() > 0) Then
            shareStringPart = spreadSheet.WorkbookPart.GetPartsOfType(Of SharedStringTablePart).First()
        Else
            shareStringPart = spreadSheet.WorkbookPart.AddNewPart(Of SharedStringTablePart)()
        End If

        ' Insert the text into the SharedStringTablePart.
        Dim index As Integer = InsertSharedStringItem(text, shareStringPart)

        ' Insert a new worksheet.
        Dim worksheetPart As WorksheetPart = InsertWorksheet(spreadSheet.WorkbookPart)

        ' Insert cell A1 into the new worksheet.
        Dim cell As Cell = InsertCellInWorksheet("A", 1, worksheetPart)

        ' Set the value of cell A1.
        cell.CellValue = New CellValue(index.ToString)
        cell.DataType = New EnumValue(Of CellValues)(CellValues.SharedString)

        ' Save the new worksheet.
        worksheetPart.Worksheet.Save()

        Return 0
    End Using
End Function

The code passes in a parameter that represents the text to insert into the cell and a parameter that represents the SharedStringTablePart object for the spreadsheet. If the ShareStringTablePart object does not contain a SharedStringTable object, the code creates one. If the text already exists in the ShareStringTable object, the code returns the index for the SharedStringItem object that represents the text. Otherwise, it creates a new SharedStringItem object that represents the text.

The following code verifies if the specified text exists in the SharedStringTablePart object and add the text if it does not exist.

C#

// Given text and a SharedStringTablePart, creates a SharedStringItem with the specified text 
// and inserts it into the SharedStringTablePart. If the item already exists, returns its index.
static int InsertSharedStringItem(string text, SharedStringTablePart shareStringPart)
{
    // If the part does not contain a SharedStringTable, create one.
    if (shareStringPart.SharedStringTable is null)
    {
        shareStringPart.SharedStringTable = new SharedStringTable();
    }

    int i = 0;

    // Iterate through all the items in the SharedStringTable. If the text already exists, return its index.
    foreach (SharedStringItem item in shareStringPart.SharedStringTable.Elements<SharedStringItem>())
    {
        if (item.InnerText == text)
        {
            return i;
        }

        i++;
    }

    // The text does not exist in the part. Create the SharedStringItem and return its index.
    shareStringPart.SharedStringTable.AppendChild(new SharedStringItem(new DocumentFormat.OpenXml.Spreadsheet.Text(text)));
    shareStringPart.SharedStringTable.Save();

    return i;
}

Visual Basic

' Given text and a SharedStringTablePart, creates a SharedStringItem with the specified text 
' and inserts it into the SharedStringTablePart. If the item already exists, returns its index.
Private Function InsertSharedStringItem(ByVal text As String, ByVal shareStringPart As SharedStringTablePart) As Integer
    ' If the part does not contain a SharedStringTable, create one.
    If (shareStringPart.SharedStringTable Is Nothing) Then
        shareStringPart.SharedStringTable = New SharedStringTable
    End If

    Dim i As Integer = 0

    ' Iterate through all the items in the SharedStringTable. If the text already exists, return its index.
    For Each item As SharedStringItem In shareStringPart.SharedStringTable.Elements(Of SharedStringItem)()
        If (item.InnerText = text) Then
            Return i
        End If
        i = (i + 1)
    Next

    ' The text does not exist in the part. Create the SharedStringItem and return its index.
    shareStringPart.SharedStringTable.AppendChild(New SharedStringItem(New DocumentFormat.OpenXml.Spreadsheet.Text(text)))
    shareStringPart.SharedStringTable.Save()

    Return i
End Function

The code adds a new WorksheetPart object to the WorkbookPart object by using the AddNewPart method. It then adds a new Worksheet object to the WorksheetPart object, and gets a unique ID for the new worksheet by selecting the maximum SheetId object used within the spreadsheet document and adding one to create the new sheet ID. It gives the worksheet a name by concatenating the word "Sheet" with the sheet ID. It then appends the new Sheet object to the Sheets collection.

The following code inserts a new Worksheet object by adding a new WorksheetPart object to the WorkbookPart object.

C#

// Given a WorkbookPart, inserts a new worksheet.
static WorksheetPart InsertWorksheet(WorkbookPart workbookPart)
{
    // Add a new worksheet part to the workbook.
    WorksheetPart newWorksheetPart = workbookPart.AddNewPart<WorksheetPart>();
    newWorksheetPart.Worksheet = new Worksheet(new SheetData());
    newWorksheetPart.Worksheet.Save();

    Sheets sheets = workbookPart.Workbook.GetFirstChild<Sheets>() ?? workbookPart.Workbook.AppendChild(new Sheets());
    string relationshipId = workbookPart.GetIdOfPart(newWorksheetPart);

    // Get a unique ID for the new sheet.
    uint sheetId = 1;
    if (sheets.Elements<Sheet>().Count() > 0)
    {
        sheetId = sheets.Elements<Sheet>().Select<Sheet, uint>(s =>
        {
            if (s.SheetId is not null && s.SheetId.HasValue)
            {
                return s.SheetId.Value;
            }

            return 0;
        }).Max() + 1;
    }

    string sheetName = "Sheet" + sheetId;

    // Append the new worksheet and associate it with the workbook.
    Sheet sheet = new Sheet() { Id = relationshipId, SheetId = sheetId, Name = sheetName };
    sheets.Append(sheet);
    workbookPart.Workbook.Save();

    return newWorksheetPart;
}

Visual Basic

' Given a WorkbookPart, inserts a new worksheet.
Private Function InsertWorksheet(ByVal workbookPart As WorkbookPart) As WorksheetPart
    ' Add a new worksheet part to the workbook.
    Dim newWorksheetPart As WorksheetPart = workbookPart.AddNewPart(Of WorksheetPart)()
    newWorksheetPart.Worksheet = New Worksheet(New SheetData)
    newWorksheetPart.Worksheet.Save()
    Dim sheets As Sheets = workbookPart.Workbook.GetFirstChild(Of Sheets)()
    Dim relationshipId As String = workbookPart.GetIdOfPart(newWorksheetPart)

    ' Get a unique ID for the new sheet.
    Dim sheetId As UInteger = 1
    If (sheets.Elements(Of Sheet).Count() > 0) Then
        sheetId = sheets.Elements(Of Sheet).Select(Function(s) s.SheetId.Value).Max() + 1
    End If

    Dim sheetName As String = ("Sheet" + sheetId.ToString())

    ' Add the new worksheet and associate it with the workbook.
    Dim sheet As Sheet = New Sheet
    sheet.Id = relationshipId
    sheet.SheetId = sheetId
    sheet.Name = sheetName
    sheets.Append(sheet)
    workbookPart.Workbook.Save()

    Return newWorksheetPart
End Function

To insert a cell into a worksheet, the code determines where to insert the new cell in the column by iterating through the row elements to find the cell that comes directly after the specified row, in sequential order. It saves that row in the refCell variable. It then inserts the new cell before the cell referenced by refCell using the InsertBefore method.

In the following code, insert a new Cell object into a Worksheet object.

C#

// Given a column name, a row index, and a WorksheetPart, inserts a cell into the worksheet. 
// If the cell already exists, returns it. 
static Cell InsertCellInWorksheet(string columnName, uint rowIndex, WorksheetPart worksheetPart)
{
    Worksheet worksheet = worksheetPart.Worksheet;
    SheetData? sheetData = worksheet.GetFirstChild<SheetData>();
    string cellReference = columnName + rowIndex;

    // If the worksheet does not contain a row with the specified row index, insert one.
    Row row;

    if (sheetData?.Elements<Row>().Where(r => r.RowIndex is not null && r.RowIndex == rowIndex).Count() != 0)
    {
        row = sheetData!.Elements<Row>().Where(r => r.RowIndex is not null && r.RowIndex == rowIndex).First();
    }
    else
    {
        row = new Row() { RowIndex = rowIndex };
        sheetData.Append(row);
    }

    // If there is not a cell with the specified column name, insert one.  
    if (row.Elements<Cell>().Where(c => c.CellReference is not null && c.CellReference.Value == columnName + rowIndex).Count() > 0)
    {
        return row.Elements<Cell>().Where(c => c.CellReference is not null && c.CellReference.Value == cellReference).First();
    }
    else
    {
        // Cells must be in sequential order according to CellReference. Determine where to insert the new cell.
        Cell? refCell = null;

        foreach (Cell cell in row.Elements<Cell>())
        {
            if (string.Compare(cell.CellReference?.Value, cellReference, true) > 0)
            {
                refCell = cell;
                break;
            }
        }

        Cell newCell = new Cell() { CellReference = cellReference };
        row.InsertBefore(newCell, refCell);

        worksheet.Save();
        return newCell;
    }
}

Visual Basic

' Given a column name, a row index, and a WorksheetPart, inserts a cell into the worksheet. 
' If the cell already exists, return it. 
Private Function InsertCellInWorksheet(ByVal columnName As String, ByVal rowIndex As UInteger, ByVal worksheetPart As WorksheetPart) As Cell
    Dim worksheet As Worksheet = worksheetPart.Worksheet
    Dim sheetData As SheetData = worksheet.GetFirstChild(Of SheetData)()
    Dim cellReference As String = (columnName + rowIndex.ToString())

    ' If the worksheet does not contain a row with the specified row index, insert one.
    Dim row As Row
    If (sheetData.Elements(Of Row).Where(Function(r) r.RowIndex.Value = rowIndex).Count() <> 0) Then
        row = sheetData.Elements(Of Row).Where(Function(r) r.RowIndex.Value = rowIndex).First()
    Else
        row = New Row()
        row.RowIndex = rowIndex
        sheetData.Append(row)
    End If

    ' If there is not a cell with the specified column name, insert one.  
    If (row.Elements(Of Cell).Where(Function(c) c.CellReference.Value = columnName + rowIndex.ToString()).Count() > 0) Then
        Return row.Elements(Of Cell).Where(Function(c) c.CellReference.Value = cellReference).First()
    Else
        ' Cells must be in sequential order according to CellReference. Determine where to insert the new cell.
        Dim refCell As Cell = Nothing
        For Each cell As Cell In row.Elements(Of Cell)()
            If (String.Compare(cell.CellReference.Value, cellReference, True) > 0) Then
                refCell = cell
                Exit For
            End If
        Next

        Dim newCell As Cell = New Cell
        newCell.CellReference = cellReference

        row.InsertBefore(newCell, refCell)
        worksheet.Save()

        Return newCell
    End If
End Function

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Sample Code

The following is the complete sample code in both C# and Visual Basic.

C#

using DocumentFormat.OpenXml;
using DocumentFormat.OpenXml.Packaging;
using DocumentFormat.OpenXml.Spreadsheet;
using System.Linq;

// Given a document name and text, 
// inserts a new work sheet and writes the text to cell "A1" of the new worksheet.
static void InsertText(string docName, string text)
{
    // Open the document for editing.
    using (SpreadsheetDocument spreadSheet = SpreadsheetDocument.Open(docName, true))
    {
        WorkbookPart workbookPart = spreadSheet.WorkbookPart ?? spreadSheet.AddWorkbookPart();

        // Get the SharedStringTablePart. If it does not exist, create a new one.
        SharedStringTablePart shareStringPart;
        if (workbookPart.GetPartsOfType<SharedStringTablePart>().Count() > 0)
        {
            shareStringPart = workbookPart.GetPartsOfType<SharedStringTablePart>().First();
        }
        else
        {
            shareStringPart = workbookPart.AddNewPart<SharedStringTablePart>();
        }

        // Insert the text into the SharedStringTablePart.
        int index = InsertSharedStringItem(text, shareStringPart);

        // Insert a new worksheet.
        WorksheetPart worksheetPart = InsertWorksheet(workbookPart);

        // Insert cell A1 into the new worksheet.
        Cell cell = InsertCellInWorksheet("A", 1, worksheetPart);

        // Set the value of cell A1.
        cell.CellValue = new CellValue(index.ToString());
        cell.DataType = new EnumValue<CellValues>(CellValues.SharedString);

        // Save the new worksheet.
        worksheetPart.Worksheet.Save();
    }
}

// Given text and a SharedStringTablePart, creates a SharedStringItem with the specified text 
// and inserts it into the SharedStringTablePart. If the item already exists, returns its index.
static int InsertSharedStringItem(string text, SharedStringTablePart shareStringPart)
{
    // If the part does not contain a SharedStringTable, create one.
    if (shareStringPart.SharedStringTable is null)
    {
        shareStringPart.SharedStringTable = new SharedStringTable();
    }

    int i = 0;

    // Iterate through all the items in the SharedStringTable. If the text already exists, return its index.
    foreach (SharedStringItem item in shareStringPart.SharedStringTable.Elements<SharedStringItem>())
    {
        if (item.InnerText == text)
        {
            return i;
        }

        i++;
    }

    // The text does not exist in the part. Create the SharedStringItem and return its index.
    shareStringPart.SharedStringTable.AppendChild(new SharedStringItem(new DocumentFormat.OpenXml.Spreadsheet.Text(text)));
    shareStringPart.SharedStringTable.Save();

    return i;
}

// Given a WorkbookPart, inserts a new worksheet.
static WorksheetPart InsertWorksheet(WorkbookPart workbookPart)
{
    // Add a new worksheet part to the workbook.
    WorksheetPart newWorksheetPart = workbookPart.AddNewPart<WorksheetPart>();
    newWorksheetPart.Worksheet = new Worksheet(new SheetData());
    newWorksheetPart.Worksheet.Save();

    Sheets sheets = workbookPart.Workbook.GetFirstChild<Sheets>() ?? workbookPart.Workbook.AppendChild(new Sheets());
    string relationshipId = workbookPart.GetIdOfPart(newWorksheetPart);

    // Get a unique ID for the new sheet.
    uint sheetId = 1;
    if (sheets.Elements<Sheet>().Count() > 0)
    {
        sheetId = sheets.Elements<Sheet>().Select<Sheet, uint>(s =>
        {
            if (s.SheetId is not null && s.SheetId.HasValue)
            {
                return s.SheetId.Value;
            }

            return 0;
        }).Max() + 1;
    }

    string sheetName = "Sheet" + sheetId;

    // Append the new worksheet and associate it with the workbook.
    Sheet sheet = new Sheet() { Id = relationshipId, SheetId = sheetId, Name = sheetName };
    sheets.Append(sheet);
    workbookPart.Workbook.Save();

    return newWorksheetPart;
}


// Given a column name, a row index, and a WorksheetPart, inserts a cell into the worksheet. 
// If the cell already exists, returns it. 
static Cell InsertCellInWorksheet(string columnName, uint rowIndex, WorksheetPart worksheetPart)
{
    Worksheet worksheet = worksheetPart.Worksheet;
    SheetData? sheetData = worksheet.GetFirstChild<SheetData>();
    string cellReference = columnName + rowIndex;

    // If the worksheet does not contain a row with the specified row index, insert one.
    Row row;

    if (sheetData?.Elements<Row>().Where(r => r.RowIndex is not null && r.RowIndex == rowIndex).Count() != 0)
    {
        row = sheetData!.Elements<Row>().Where(r => r.RowIndex is not null && r.RowIndex == rowIndex).First();
    }
    else
    {
        row = new Row() { RowIndex = rowIndex };
        sheetData.Append(row);
    }

    // If there is not a cell with the specified column name, insert one.  
    if (row.Elements<Cell>().Where(c => c.CellReference is not null && c.CellReference.Value == columnName + rowIndex).Count() > 0)
    {
        return row.Elements<Cell>().Where(c => c.CellReference is not null && c.CellReference.Value == cellReference).First();
    }
    else
    {
        // Cells must be in sequential order according to CellReference. Determine where to insert the new cell.
        Cell? refCell = null;

        foreach (Cell cell in row.Elements<Cell>())
        {
            if (string.Compare(cell.CellReference?.Value, cellReference, true) > 0)
            {
                refCell = cell;
                break;
            }
        }

        Cell newCell = new Cell() { CellReference = cellReference };
        row.InsertBefore(newCell, refCell);

        worksheet.Save();
        return newCell;
    }
}

Visual Basic

Imports DocumentFormat.OpenXml
Imports DocumentFormat.OpenXml.Packaging
Imports DocumentFormat.OpenXml.Spreadsheet


Module MyModule

    Sub Main(args As String())
        InsertText(args(0), args(1))
    End Sub

    ' Given a document name and text, 
    ' inserts a new worksheet and writes the text to cell "A1" of the new worksheet.
    Public Function InsertText(ByVal docName As String, ByVal text As String)
        ' Open the document for editing.
        Dim spreadSheet As SpreadsheetDocument = SpreadsheetDocument.Open(docName, True)

        Using (spreadSheet)
            ' Get the SharedStringTablePart. If it does not exist, create a new one.
            Dim shareStringPart As SharedStringTablePart

            If (spreadSheet.WorkbookPart.GetPartsOfType(Of SharedStringTablePart).Count() > 0) Then
                shareStringPart = spreadSheet.WorkbookPart.GetPartsOfType(Of SharedStringTablePart).First()
            Else
                shareStringPart = spreadSheet.WorkbookPart.AddNewPart(Of SharedStringTablePart)()
            End If

            ' Insert the text into the SharedStringTablePart.
            Dim index As Integer = InsertSharedStringItem(text, shareStringPart)

            ' Insert a new worksheet.
            Dim worksheetPart As WorksheetPart = InsertWorksheet(spreadSheet.WorkbookPart)

            ' Insert cell A1 into the new worksheet.
            Dim cell As Cell = InsertCellInWorksheet("A", 1, worksheetPart)

            ' Set the value of cell A1.
            cell.CellValue = New CellValue(index.ToString)
            cell.DataType = New EnumValue(Of CellValues)(CellValues.SharedString)

            ' Save the new worksheet.
            worksheetPart.Worksheet.Save()

            Return 0
        End Using
    End Function

    ' Given text and a SharedStringTablePart, creates a SharedStringItem with the specified text 
    ' and inserts it into the SharedStringTablePart. If the item already exists, returns its index.
    Private Function InsertSharedStringItem(ByVal text As String, ByVal shareStringPart As SharedStringTablePart) As Integer
        ' If the part does not contain a SharedStringTable, create one.
        If (shareStringPart.SharedStringTable Is Nothing) Then
            shareStringPart.SharedStringTable = New SharedStringTable
        End If

        Dim i As Integer = 0

        ' Iterate through all the items in the SharedStringTable. If the text already exists, return its index.
        For Each item As SharedStringItem In shareStringPart.SharedStringTable.Elements(Of SharedStringItem)()
            If (item.InnerText = text) Then
                Return i
            End If
            i = (i + 1)
        Next

        ' The text does not exist in the part. Create the SharedStringItem and return its index.
        shareStringPart.SharedStringTable.AppendChild(New SharedStringItem(New DocumentFormat.OpenXml.Spreadsheet.Text(text)))
        shareStringPart.SharedStringTable.Save()

        Return i
    End Function

    ' Given a WorkbookPart, inserts a new worksheet.
    Private Function InsertWorksheet(ByVal workbookPart As WorkbookPart) As WorksheetPart
        ' Add a new worksheet part to the workbook.
        Dim newWorksheetPart As WorksheetPart = workbookPart.AddNewPart(Of WorksheetPart)()
        newWorksheetPart.Worksheet = New Worksheet(New SheetData)
        newWorksheetPart.Worksheet.Save()
        Dim sheets As Sheets = workbookPart.Workbook.GetFirstChild(Of Sheets)()
        Dim relationshipId As String = workbookPart.GetIdOfPart(newWorksheetPart)

        ' Get a unique ID for the new sheet.
        Dim sheetId As UInteger = 1
        If (sheets.Elements(Of Sheet).Count() > 0) Then
            sheetId = sheets.Elements(Of Sheet).Select(Function(s) s.SheetId.Value).Max() + 1
        End If

        Dim sheetName As String = ("Sheet" + sheetId.ToString())

        ' Add the new worksheet and associate it with the workbook.
        Dim sheet As Sheet = New Sheet
        sheet.Id = relationshipId
        sheet.SheetId = sheetId
        sheet.Name = sheetName
        sheets.Append(sheet)
        workbookPart.Workbook.Save()

        Return newWorksheetPart
    End Function

    ' Given a column name, a row index, and a WorksheetPart, inserts a cell into the worksheet. 
    ' If the cell already exists, return it. 
    Private Function InsertCellInWorksheet(ByVal columnName As String, ByVal rowIndex As UInteger, ByVal worksheetPart As WorksheetPart) As Cell
        Dim worksheet As Worksheet = worksheetPart.Worksheet
        Dim sheetData As SheetData = worksheet.GetFirstChild(Of SheetData)()
        Dim cellReference As String = (columnName + rowIndex.ToString())

        ' If the worksheet does not contain a row with the specified row index, insert one.
        Dim row As Row
        If (sheetData.Elements(Of Row).Where(Function(r) r.RowIndex.Value = rowIndex).Count() <> 0) Then
            row = sheetData.Elements(Of Row).Where(Function(r) r.RowIndex.Value = rowIndex).First()
        Else
            row = New Row()
            row.RowIndex = rowIndex
            sheetData.Append(row)
        End If

        ' If there is not a cell with the specified column name, insert one.  
        If (row.Elements(Of Cell).Where(Function(c) c.CellReference.Value = columnName + rowIndex.ToString()).Count() > 0) Then
            Return row.Elements(Of Cell).Where(Function(c) c.CellReference.Value = cellReference).First()
        Else
            ' Cells must be in sequential order according to CellReference. Determine where to insert the new cell.
            Dim refCell As Cell = Nothing
            For Each cell As Cell In row.Elements(Of Cell)()
                If (String.Compare(cell.CellReference.Value, cellReference, True) > 0) Then
                    refCell = cell
                    Exit For
                End If
            Next

            Dim newCell As Cell = New Cell
            newCell.CellReference = cellReference

            row.InsertBefore(newCell, refCell)
            worksheet.Save()

            Return newCell
        End If
    End Function

End Module

See also

Open XML SDK class library reference