' Given a document name, a worksheet name, and a cell name, get the column of the cell and return
    ' the content of the first cell in that column.
    Public Function XLGetColumnHeader(ByVal docName As String, _
        ByVal worksheetName As String, ByVal cellName As String) As String
 
        Dim returnValue As String = Nothing
 
        ' Open the document as read-only.
        Using document As SpreadsheetDocument = SpreadsheetDocument.Open(docName, False)
            Dim wbPart As WorkbookPart = document.WorkbookPart
 
            ' Given a worksheet name, first find the Sheet that corresponds to the name.
            Dim sheet = wbPart.Workbook.Descendants(Of Sheet)(). _
              Where(Function(s) s.Name = worksheetName).FirstOrDefault
            If sheet Is Nothing Then
                ' The specified worksheet does not exist.
                Return Nothing
            End If
 
            ' Given the Sheet, 
            Dim worksheetPart As WorksheetPart = CType(wbPart.GetPartById(sheet.Id), WorksheetPart)
 
            ' Get the column name for the specified cell.
            Dim columnName As String = GetColumnName(cellName)
 
            ' Get the cells in the specified column and order them by row.
            Dim headCell = worksheetPart.Worksheet.Descendants(Of Cell)(). _
              Where(Function(c) String.Compare(GetColumnName(c.CellReference.Value), columnName, True) = 0). _
              OrderBy(Function(r) GetRowIndex(r.CellReference)).FirstOrDefault()
 
            If headCell Is Nothing Then
                ' The specified column does not exist.
                Return Nothing
            End If
 
            ' If the content of the first cell is stored as a shared string, get the text of the first cell
            ' from the SharedStringTablePart and return it. Otherwise, return the string value of the cell.
            If headCell.DataType IsNot Nothing AndAlso headCell.DataType.Value = CellValues.SharedString Then
                Dim sharedStringPart As SharedStringTablePart = wbPart.GetPartsOfType(Of SharedStringTablePart)().FirstOrDefault()
                If sharedStringPart IsNot Nothing Then
                    Dim items = sharedStringPart.SharedStringTable.Elements(Of SharedStringItem)()
                    returnValue = items.ElementAt(Integer.Parse(headCell.CellValue.Text)).InnerText
                End If
            Else
                returnValue = headCell.CellValue.Text
            End If
        End Using
        Return returnValue
    End Function
 
    ' Given a cell name, parses the specified cell to get the column name.
    Private Function GetColumnName(ByVal cellName As String) As String
        ' Create a regular expression to match the column name portion of the cell name.
        Dim regex As Regex = New Regex("[A-Za-z]+")
        Dim match As Match = regex.Match(cellName)
        Return match.Value
    End Function
 
    ' Given a cell name, parses the specified cell to get the row index.
    Private Function GetRowIndex(ByVal cellName As String) As UInteger
        ' Create a regular expression to match the row index portion the cell name.
        Dim regex As Regex = New Regex("\d+")
        Dim match As Match = regex.Match(cellName)
        Return UInteger.Parse(match.Value)
    End Function

' get a list of column headers.
    Public Function XLColumnList(ByVal fileName As String, ByVal worksheetName As String) As List(Of String)
        'Declare variable TO HOLd list of column headers
        Dim Headers As List(Of String) = New List(Of String)
 
        'declare variable to hold the alphabet & a letter number
        Dim Alphabet() As String = {"A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M", "N", "O", _
                                  "P", "Q", "R", "S", "T", "U", "V", "W", "X", "Y", "Z"}
 
        'Variable to hold the current index for the alphabet array
        Dim AlphabetIndex As Integer = 0
 
        'Declare variable to count which iteration of the alphabet the loop is on
        Dim AlphabetCount As Integer = 0
 
 
        'variable to hold last column header name and give it a value so the loop will start
        Dim LastHeader As String = "None"
 
 
        While Not LastHeader Is Nothing
 
            Select Case AlphabetCount
                Case 0 To 26
                    LastHeader = XLGetColumnHeader(fileName, worksheetName, Alphabet(AlphabetIndex) + "1")
                Case 27 To 52
                    LastHeader = XLGetColumnHeader(fileName, worksheetName, "A" + Alphabet(AlphabetIndex) + "1")
                Case 52 To 78
                    LastHeader = XLGetColumnHeader(fileName, worksheetName, "B" + Alphabet(AlphabetIndex) + "1")
                Case 79 To 104
                    LastHeader = XLGetColumnHeader(fileName, worksheetName, "C" + Alphabet(AlphabetIndex) + "1")
                Case 105 To 130
                    LastHeader = XLGetColumnHeader(fileName, worksheetName, "D" + Alphabet(AlphabetIndex) + "1")
                Case 131 To 156
                    LastHeader = XLGetColumnHeader(fileName, worksheetName, "E" + Alphabet(AlphabetIndex) + "1")
                Case 157 To 182
                    LastHeader = XLGetColumnHeader(fileName, worksheetName, "F" + Alphabet(AlphabetIndex) + "1")
            End Select
 
            If Not LastHeader Is Nothing Then
                Headers.Add(LastHeader)
            End If
            AlphabetCount = AlphabetCount + 1
            If AlphabetIndex < 25 Then
                AlphabetIndex = AlphabetIndex + 1
            Else
                AlphabetIndex = 0
            End If
            If AlphabetCount > 182 Then
                Headers.Add("Exceeded 182 column limit")
                LastHeader = Nothing
            End If
        End While
        If Headers Is Nothing Then
            Headers.Add("No column headers.")
        End If
        Return Headers
    End Function

            Dim headCell = worksheetPart.Worksheet.Descendants(Of Cell)(). _
              Where(Function(c) String.Compare(GetColumnName(c.CellReference.Value), columnName, True) = 0). _
              OrderBy(Function(r) GetRowIndex(r.CellReference)).FirstOrDefault()