查找字符并在文件中插入新行

Question

我希望逐行读取文件，一旦到达第 65 至 67 列中不包含相同字符的行，我想在其上方的第 2 行插入一个字符串行。我正在使用 VB.NET

到目前为止，我已经编写了逐行读取文件的代码。 我不确定如何将字符串行插入到第 65-67 列中的字符不同的文件中 任何帮助都会很棒。谢谢

   Protected Sub UploadFile(sender As Object, e As EventArgs)
    Dim fileName As String = Path.GetFileName(FileUpload1.PostedFile.FileName)
    Dim filePath As String = Server.MapPath("~/Files/") & fileName
    FileUpload1.SaveAs(filePath)

    '--Read block of lines then insert line for each new block
    For Each line In IO.File.ReadLines(filePath)
        'If line.Substring(65, 3) <> " " Then '<> to previous substring

            '--Insert new line 

        'End If
    Next

End Sub



 <asp:FileUpload ID="FileUpload1" runat="server" />
 <asp:Button ID="Button1" Text="Upload File" runat="server" OnClick="UploadFile" />

Answer 1

像这样的东西。

    Dim lines As List(Of String) = IO.File.ReadLines(filePath).ToList
    Dim idx As Integer = 0
    Do While idx < lines.Count - 2
        Dim thisLine As String = lines(idx)
        Dim nextLine As String = lines(idx + 1)
        If thisLine.Substring(65, 3) <> nextLine.Substring(65, 3) Then
            lines.Insert(idx + 1, "NEW BLOCK")
            idx += 1
        End If
        idx += 1
    Loop
    Dim foo As String = String.Join(ControlChars.Cr, lines)
    IO.File.WriteAllText("path", foo)

编辑 - 基于 cmets

    Dim lines As List(Of String) = IO.File.ReadLines(filePath).ToList
    Dim idx As Integer = 0
    Do While idx < lines.Count - 2
        Dim thisLine As String = lines(idx)
        Dim nextLine As String = lines(idx + 1)
        Dim key As String = thisLine.Substring(65, 3).Trim
        If key <> nextLine.Substring(65, 3) AndAlso
                key = "" Then
            lines.Insert(idx + 1, "NEW BLOCK")
            idx += 1
        End If
        idx += 1
    Loop
    Dim foo As String = String.Join(ControlChars.Cr, lines)
    IO.File.WriteAllText("path", foo)