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Asp.net PrependText而不是AppendText?_Asp.net_Vb.net - Fatal编程技术网

Asp.net PrependText而不是AppendText?

Asp.net PrependText而不是AppendText?,asp.net,vb.net,Asp.net,Vb.net,我正在使用下面的代码将一些文本写入文件。有没有一种方法可以代替使用AppendText来预处理写入文本文件的新数据?因此,不是将最新条目写入底部,而是将其写入文本文档的顶部 Public filePath As String = "c:\path\log.txt" Public w As StreamWriter w = File.AppendText(filePath) w.WriteLine('Blah Blah') w.Flush() w.Close() 对于大

我正在使用下面的代码将一些文本写入文件。有没有一种方法可以代替使用AppendText来预处理写入文本文件的新数据?因此,不是将最新条目写入底部,而是将其写入文本文档的顶部

Public filePath As String = "c:\path\log.txt"
Public w As StreamWriter

w = File.AppendText(filePath)
    w.WriteLine('Blah Blah')
    w.Flush()
    w.Close()

对于大多数常见的文件系统,不需要。您必须复制该文件。

您可以通过这种方式对其进行预处理

Dim txtList As New List(Of String)

txtList.Add("top line of text")

Using sr As New StreamReader("c:\path\log.txt")
  While Not sr.EndOfStream()     
    txtList.Add(sr.ReadLine)
  End While
End Using

Using sw As New StreamWriter("c:\path\log.txt")
  For Each line As String In txtList
    sw.WriteLine(line)
  Next
End Using