Question

我写了一个ashx来构建一个excel文件，从我的数据库中导出一些数据。当我打开文件时，我的消息说：您尝试打开的文件格式与指定的文件扩展名不同...

这是我的代码：

Imports System.Web

导入System.Web.Services Imports System.IO

公共类DowloadClient 实现System.Web.IHttpHandler

Sub ProcessRequest(ByVal context As HttpContext) Implements IHttpHandler.ProcessRequest

    'set header
    context.Response.Clear()
    context.Response.AddHeader("content-disposition", "attachment; filename=Clients.xls")
    context.Response.ContentType = "application/ms-excel"
    context.Response.ContentEncoding = Encoding.UTF8

    Dim exportContent As String = ExportToExcel()
    context.Response.Write(exportContent)

    'write the file
    context.Response.End()

End Sub

Private Function ExportToExcel() As String

    Dim _exportContent As String = ""

    Dim q = GetClientsCRM(New NatCallEntities)
    Using sb As New IO.StringWriter()

        Using htmlWriter As New HtmlTextWriter(sb)

            Dim table As New WebControls.Table()
            table.GridLines = GridLines.Horizontal
            table.BorderWidth = New Unit(1)

            Dim header As New TableRow()
            header.BackColor = Drawing.Color.Gray

            Dim h As New TableCell()
            h.BorderWidth = New Unit(1)
            h.Text = "Nom"
            header.Cells.Add(h)
            Dim h1 As New TableCell()
            h1.BorderWidth = New Unit(1)
            h1.Text = "PreNom"
            header.Cells.Add(h1)
            Dim h2 As New TableCell()
            h2.BorderWidth = New Unit(1)
            h2.Text = "Conjoint"
            header.Cells.Add(h2)
            Dim h3 As New TableCell()
            h3.BorderWidth = New Unit(1)
            h3.Text = "Proprietaire Adresse"
            header.Cells.Add(h3)
            Dim h4 As New TableCell()
            h4.BorderWidth = New Unit(1)
            h4.Text = "Mention Adresse"
            header.Cells.Add(h4)
            Dim h5 As New TableCell()
            h5.BorderWidth = New Unit(1)
            h5.Text = "Adresse"
            header.Cells.Add(h5)
            Dim h6 As New TableCell()
            h6.BorderWidth = New Unit(1)
            h6.Text = "Complement Adresse"
            header.Cells.Add(h6)
            Dim h7 As New TableCell()
            h7.BorderWidth = New Unit(1)
            h7.Text = "Code Postale"
            header.Cells.Add(h7)
            Dim h8 As New TableCell()
            h8.BorderWidth = New Unit(1)
            h8.Text = "Ville"
            header.Cells.Add(h8)
            Dim h9 As New TableCell()
            h9.BorderWidth = New Unit(1)
            h9.Text = "Telephone"
            header.Cells.Add(h9)
            Dim h10 As New TableCell()
            h10.BorderWidth = New Unit(1)
            h10.Text = "Representant"
            header.Cells.Add(h10)

            table.Rows.Add(header)

            If q IsNot Nothing AndAlso q.Count > 0 Then
                Dim i As Integer = 0
                For Each clt In q

                    Dim row As New TableRow()
                    Dim cell As New TableCell()
                    cell.BorderWidth = New Unit(1)
                    cell.Text = HttpUtility.HtmlEncode(clt.Nom)
                    row.Cells.Add(cell)
                    Dim cell1 As New TableCell()
                    cell1.BorderWidth = New Unit(1)
                    cell1.Text = HttpUtility.HtmlEncode(clt.Prenom)
                    row.Cells.Add(cell1)
                    Dim cell2 As New TableCell()
                    cell2.BorderWidth = New Unit(1)
                    cell2.Text = HttpUtility.HtmlEncode(clt.Conjoint)
                    row.Cells.Add(cell2)
                    Dim cell3 As New TableCell()
                    cell3.BorderWidth = New Unit(1)
                    cell3.Text = HttpUtility.HtmlEncode(clt.Proprietaire)
                    row.Cells.Add(cell3)
                    Dim cell4 As New TableCell()
                    cell4.BorderWidth = New Unit(1)
                    cell4.Text = HttpUtility.HtmlEncode(clt.Mention)
                    row.Cells.Add(cell4)
                    Dim cell5 As New TableCell()
                    cell5.BorderWidth = New Unit(1)
                    cell5.Text = HttpUtility.HtmlEncode(clt.Adresse)
                    row.Cells.Add(cell5)
                    Dim cell6 As New TableCell()
                    cell6.BorderWidth = New Unit(1)
                    cell6.Text = HttpUtility.HtmlEncode(clt.Complement)
                    row.Cells.Add(cell6)
                    Dim cell7 As New TableCell()
                    cell7.BorderWidth = New Unit(1)
                    cell7.Text = clt.CP
                    row.Cells.Add(cell7)
                    Dim cell8 As New TableCell()
                    cell8.BorderWidth = New Unit(1)
                    cell8.Text = HttpUtility.HtmlEncode(clt.Ville)
                    row.Cells.Add(cell8)
                    Dim cell9 As New TableCell()
                    cell9.BorderWidth = New Unit(1)
                    cell9.Text = clt.Tel
                    row.Cells.Add(cell9)
                    Dim cell10 As New TableCell()
                    cell10.BorderWidth = New Unit(1)
                    cell10.Text = HttpUtility.HtmlEncode(clt.Representant)
                    row.Cells.Add(cell10)
                    table.Rows.Add(row)
                Next
            End If

            table.RenderControl(htmlWriter)
            _exportContent = sb.ToString()
        End Using
    End Using
    Return _exportContent

End Function

ReadOnly Property IsReusable() As Boolean Implements IHttpHandler.IsReusable
    Get
        Return False
    End Get
End Property

End Class

当我打开文件时，一切都很好。如果没有这条消息我该怎么办？

Answer 1

最后我找到了一个好的图书馆：EPPLUS

格式化Excel文件以将数据导出到vb.net中的ashx中的Excel

1 个答案: