Member Avatar for kRod

Good Day all,
My question is When I get the schema of an EXCEL worksheet with Column headers I get what's expected the names of the columns but when I get the schema of a worksheet without headers I get the first row of data as the Column Names. The trouble is in determining if a worksheet has headers or not, so as to program my connection string correctly. Anyone have thoughts on this? I created a worksheet with the schema as it is in the dataView.

Thank you
KRod

Edited by kRod
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Good quick fix from — adding a checkbox is practical for edge cases, but it breaks full automation. was right to clarify the goal. A reliable automated approach is: read the sheet once with HDR=NO (so the first row comes back as data), grab the first 2–5 rows, then apply simple heuristics per column to vote whether the first row looks like a header. If most columns vote "header", treat row 1 as headers and re-open / rename columns accordingly.

Here’s a compact VB.NET example that implements that idea (reads a few rows with HDR=NO, compares types/patterns between row1 and row2, and returns True if the first row is probably a header):

Function DetectHasHeader(excelFile As String, sheetName As String) As Boolean
    Dim connStr As String
    If excelFile.EndsWith(".xlsx", StringComparison.OrdinalIgnoreCase) OrElse excelFile.EndsWith(".xlsm", StringComparison.OrdinalIgnoreCase) Then
        connStr = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" & excelFile & ";Extended Properties=""Excel 12.0 Xml;HDR=NO;IMEX=1;"""
    Else
        connStr = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" & excelFile & ";Extended Properties=""Excel 8.0;HDR=NO;IMEX=1;"""
    End If

    Dim dt As New DataTable()
    Using conn As New System.Data.OleDb.OleDbConnection(connStr)
        conn.Open()
        Using da As New System.Data.OleDb.OleDbDataAdapter(String.Format("SELECT TOP 5 * FROM [{0}$]", sheetName), conn)
            da.Fill(dt)
        End Using
    End Using

    If dt.Rows.Count < 2 Then Return False
    Dim row0 = dt.Rows(0), row1 = dt.Rows(1)
    Dim headerVotes As Integer = 0, analyzable As Integer = 0

    For Each col As DataColumn In dt.Columns
        Dim a As String = If(row0(col) Is DBNull.Value, String.Empty, row0(col).ToString().Trim())
        Dim b As String = If(row1(col) Is DBNull.Value, String.Empty, row1(col).ToString().Trim())
        If a = "" AndAlso b = "" Then Continue For
        If String.Equals(a, b, StringComparison.OrdinalIgnoreCase) Then Continue For

        analyzable += 1
        Dim aNum, bNum As Double
        Dim aIsNum = Double.TryParse(a, aNum), bIsNum = Double.TryParse(b, bNum)
        Dim aDate, bDate As DateTime
        Dim aIsDate = DateTime.TryParse(a, aDate), bIsDate = DateTime.TryParse(b, bDate)

        If (Not aIsNum AndAlso bIsNum) OrElse (Not aIsDate AndAlso bIsDate) Then headerVotes += 1
        If a.Length > 0 AndAlso a.Length < 40 AndAlso a.Length < b.Length Then headerVotes += 1
    Next

    If analyzable = 0 Then Return False
    Return (headerVotes / analyzable) >= 0.6
End Function

Notes and caveats: Excel/OLEDB type inference (IMEX, HDR) and mixed-type columns can still mislead the heuristic. If sheets contain many string-only columns (e.g., lists of names) the detector may be uncertain — fall back to asking the user in those cases or use a stronger rule set (check for common header words like "Name", "ID", "Date"). For maximum control in automation, consider reading cells with OpenXML/ClosedXML/EPPlus instead of OLEDB; they expose actual cell types and let you apply richer rules.

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Member Avatar for Stuugie

I'm not really sure what you're asking here. You wish to check to see if there are headers in an Excel file with VB.NET?

Member Avatar for kRod

That's it exactly.

Member Avatar for kRod

Well I have come to the conclusion: Added a CheckBox to the Form for Has or HasNot Column Names, Let user Preview the WorkSheet, set Connection String from that. Kind of ruins any automation though.

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