在VB.net中读取Excel文件时出现问题

Question

我一直在尝试上传和读取Excel文件（.xls或.xlsx）

我使用以下代码成功上传：

Protected Sub btnUpload_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles    btnUpload.Click
    Dim filepath As String = ""
    If FileUpload1.HasFile Then
        Try
            Dim filename As String = FileUpload1.PostedFile.FileName
            Dim extension = (filename.Substring(filename.LastIndexOf("."), (filename.Length() - filename.LastIndexOf("."))))
            If extension = ".xlsx" Or extension = ".xls" Then
                filepath = "\" & Common.toUnix(Now) & "_" & filename
                FileUpload1.SaveAs(Server.MapPath("~/") & filepath)
                  ' ====   NOW READ THE FILE
            Else
                StatusLabel.InnerText = "Only Excel file types are accepted (.xls/.xlsx)<br> File Uploaded had extension: " & extension
            End If

        Catch ex As Exception
            StatusLabel.InnerText = "Upload status: The file could not be uploaded. The following error occured: " + ex.ToString()
        End Try

    End If
End Sub

它上传OK，但在尝试读取文件时出现此错误：

System.Data.OleDb.OleDbException (0x80004005): The Microsoft Jet database engine cannot open the file ''. It is already opened exclusively by another user, or you need permission to view its data.

我使用的代码与此类似：

vb.net traversing an xls / xlsx file?

因此连接如下：

 Dim connString As String = "Provider=Microsoft.Jet.OLEDB.4.0" & _
                           ";Data Source=" & ExcelFile & _
                           ";Extended Properties=Excel 8.0;"

    Dim conn As OleDbConnection = Nothing
    Dim dt As System.Data.DataTable = Nothing
    Dim excelDataSet As New DataSet()

    Try

        conn = New OleDbConnection(connString)

        conn.Open()  '<<< ERROR IS RAISED ON THIS LINE
        dt = conn.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, Nothing)
        If dt Is Nothing Then
            Return Nothing
        End If

        Dim excelSheets(dt.Rows.Count) As String
        Dim i As Integer = 0
        For Each row As DataRow In dt.Rows
            excelSheets(i) = row("payments").ToString
            System.Math.Min(System.Threading.Interlocked.Increment(i), i - 1)
            If i = SheetNumber Then
                Exit For
            End If
        Next

     ..................

我正在上传到共享服务器，因此无法控制权限，但我确实具有读/写权限并且上传图像工作正常，但它正在读取此文件，我无法工作。

注意

.xls文件时出现此错误，使用.xlsx时出现此错误：

System.Data.OleDb.OleDbException (0x80004005): Cannot update. Database or object is read-only. at System.Data.OleDb.OleDbConnectionInternal

此行发生此错误：

 For Each row As DataRow In dt.Rows

所以看起来它正在上传并打开文件OK，但没有读取行....

我不确定为什么会发生这种情况！

任何帮助将非常感激！

Answer 1

ACE是残酷的，一直有麻烦，它不能同时存在于32位和64位版本的系统上。结果我根本就不使用它。

要读取Excel XLSX文件，我使用“EPPlus”，这已被证明非常容易处理和极其高效。

它只适用于XLSX（不是XLS）

示例...（简单地将第一张纸拉出作为数据表）

    Public Function XlsxToDataTable(byteStream As IO.MemoryStream) As DataTable
        Using pac As New OfficeOpenXml.ExcelPackage(byteStream)
            Dim wb As OfficeOpenXml.ExcelWorkbook = pac.Workbook
            Dim ws As OfficeOpenXml.ExcelWorksheet = wb.Worksheets(1) '1 based
            Dim out As New DataTable
            For iC As Integer = 1 To ws.Dimension.End.Column
                out.Columns.Add(ws.Cells(1, iC).Value.ToString)
            Next
            For iR As Integer = 2 To ws.Dimension.End.Row
                Dim nr As DataRow = out.NewRow
                For iC As Integer = 1 To ws.Dimension.End.Column
                    nr(iC - 1) = ws.Cells(iR, iC).Value
                Next
                out.Rows.Add(nr)
            Next
            Return out
        End Using
    End Function