Vb.net Visual Basic 2010中的文件夹更改监视器无法正确写入更改

我在VisualBasic2010中制作了一个程序，可以监视和记录文件夹中的更改，例如文件删除、文件重命名、文件创建时间以及哪些文件，但这是一个问题。我写代码是为了在进行另一次更改时生成一行新行，当进行更改时，它会将其写入一个名为log.txt的文件，但日志看起来只是“file log.txt has modified”，因为程序在写入日志更改时，会将log.txt更改为写入日志，但奇怪的是，它会删除文档中的所有内容，并写入“File log..txt已被修改”，即使我在写入之前已在代码中写入新行。有人能帮我解决这个问题吗？代码如下：

Imports System.IO
Imports System.Diagnostics
Public Class Form1
Public watchfolder As FileSystemWatcher

Private Sub Button1_Click(sender As System.Object, e As System.EventArgs) Handles Button1.Click

    watchfolder = New System.IO.FileSystemWatcher()

    'this is the path we want to monitor
    watchfolder.Path = TextBox1.Text

    'Add a list of Filter we want to specify
    'make sure you use OR for each Filter as we need to
    'all of those 

    watchfolder.NotifyFilter = IO.NotifyFilters.DirectoryName
    watchfolder.NotifyFilter = watchfolder.NotifyFilter Or _
                               IO.NotifyFilters.FileName
    watchfolder.NotifyFilter = watchfolder.NotifyFilter Or _
                               IO.NotifyFilters.Attributes

    ' add the handler to each event
    AddHandler watchfolder.Changed, AddressOf logchange
    AddHandler watchfolder.Created, AddressOf logchange
    AddHandler watchfolder.Deleted, AddressOf logchange

    ' add the rename handler as the signature is different
    AddHandler watchfolder.Renamed, AddressOf logrename

    'Set this property to true to start watching
    watchfolder.EnableRaisingEvents = True

    Button1.Enabled = False
    Button2.Enabled = True

    'End of code for btn_start_click
End Sub
Private Sub logchange(ByVal source As Object, ByVal e As  _
                    System.IO.FileSystemEventArgs)
    If e.ChangeType = IO.WatcherChangeTypes.Changed Then
        Dim writer As New IO.StreamWriter("log.txt")
        writer.WriteLine(Chr(13) & "File" + " " + e.FullPath + " " + "has been modified")
        writer.Close()
    End If
    If e.ChangeType = IO.WatcherChangeTypes.Created Then
        Dim writer As New IO.StreamWriter("log.txt")
        writer.WriteLine(Chr(13) & "File" + " " + e.FullPath + " " + "has been created")
        writer.Close()
    End If
    If e.ChangeType = IO.WatcherChangeTypes.Deleted Then
        Dim writer As New IO.StreamWriter("log.txt")
        writer.WriteLine(Chr(13) & "Filde" + " " + e.FullPath + " " + "has been deleted")
        writer.Close()
    End If
End Sub
Public Sub logrename(ByVal source As Object, ByVal e As  _
                        System.IO.RenamedEventArgs)
    Dim writer As New IO.StreamWriter("log.txt")
    writer.WriteLine(Chr(13) & "File" + " " + e.FullPath + "has been renamed to" + " " + e.Name)
    writer.Close()
End Sub

Private Sub Button2_Click(sender As System.Object, e As System.EventArgs) Handles Button2.Click
    ' Stop watching the folder
    watchfolder.EnableRaisingEvents = False
    Button1.Enabled = True
    Button2.Enabled = False
End Sub

End Class

---

打开streamwriter时，您没有告诉它追加，因此它会覆盖：

Dim writer As New IO.StreamWriter("log.txt", True)

此外，您不需要为每个活动创建新的流：

Dim msg as string= Environment.NewLine & "File " & e.FullPath & " "
Select case e.ChangeType
      case IO.WatcherChangeTypes.Created 
         msg &= "has been created"

      case IO.WatcherChangeTypes.Deleted
         msg &= "has been deleted"
      ...etc
 End Select

 Dim writer As New IO.StreamWriter("log.txt", True)
 writer.WriteLine(msg)
 writer.Close()

…您也可以让流保持打开状态，直到观察者结束

您可能应该免除对log.txt的日志更改，因此测试

e.FullPath

：

 If System.Io.Path.GetFileName(e.FullPath).ToLower = "log.text" Then Exit Sub

---

现在程序开始工作了！感谢MPelletier和Proputinix提供的惊人帮助！以下是完整的代码：

 Imports System.IO
 Imports System.Diagnostics
 Public Class Form1

Public watchfolder As FileSystemWatcher

Private Sub Button1_Click(sender As System.Object, e As System.EventArgs) Handles Button1.Click

    watchfolder = New System.IO.FileSystemWatcher()
    watchfolder.IncludeSubdirectories = True

    watchfolder.Path = TextBox1.Text



    watchfolder.NotifyFilter = IO.NotifyFilters.DirectoryName
    watchfolder.NotifyFilter = watchfolder.NotifyFilter Or _
                               IO.NotifyFilters.FileName
    watchfolder.NotifyFilter = watchfolder.NotifyFilter Or _
                               IO.NotifyFilters.Attributes


    AddHandler watchfolder.Changed, AddressOf logchange
    AddHandler watchfolder.Created, AddressOf logchange
    AddHandler watchfolder.Deleted, AddressOf logchange


    AddHandler watchfolder.Renamed, AddressOf logrename


    watchfolder.EnableRaisingEvents = True

    Button1.Enabled = False
    Button2.Enabled = True


End Sub
Private Sub logchange(ByVal source As Object, ByVal e As  _
                    System.IO.FileSystemEventArgs)
    If System.IO.Path.GetFileName(e.FullPath).ToLower = "log.txt" Then Exit Sub
    Dim msg As String = Environment.NewLine & "File " & e.FullPath & " "

    Select Case e.ChangeType
        Case IO.WatcherChangeTypes.Created
            msg &= "has been created" + "  " + "Time:" + " " + Format(TimeOfDay)

        Case IO.WatcherChangeTypes.Deleted
            msg &= "has been deleted" + "  " + "Time:" + " " + Format(TimeOfDay)

        Case IO.WatcherChangeTypes.Changed
            msg &= "has been modified" + "  " + "Time:" + " " + Format(TimeOfDay)

    End Select

    Dim writer As New IO.StreamWriter("log.txt", True)
    writer.WriteLine(msg)
    writer.Close()
End Sub
Public Sub logrename(ByVal source As Object, ByVal e As  _
                        System.IO.RenamedEventArgs)
    Select e.ChangeType
        Case IO.WatcherChangeTypes.Created
            Exit Sub
        Case IO.WatcherChangeTypes.Changed
            Exit Sub
        Case IO.WatcherChangeTypes.Deleted
            Exit Sub
        Case Else
            Dim msgrn As String = Environment.NewLine & "File " + e.OldName + " "
            msgrn &= "has been renamed to" + " " + e.Name + "  " + "Time:" + " " + Format(TimeOfDay)
            Dim writer As New IO.StreamWriter("log.txt", True)
            writer.WriteLine(msgrn)
            writer.Close()
    End Select

End Sub

Private Sub Button2_Click(sender As System.Object, e As System.EventArgs) Handles Button2.Click

    watchfolder.EnableRaisingEvents = False
    Button1.Enabled = True
    Button2.Enabled = False
End Sub

Private Sub Button3_Click(sender As System.Object, e As System.EventArgs) Handles Button3.Click
    Me.Hide()
    MsgBox("To close it later, don't open the program again, press CTRL+ALT+DELETE and press Start Task Manager or something like that, and go to processes and kill FolderMonitor.exe or what you have named the file", 0 + 64, "FolderMonitor")
End Sub
End Class

---

你好谢谢你的帮助！当我使用您的代码时，我的程序工作得更好，然后我在代码中添加了一些小东西，使其工作得更完美！：）但问题是，它不监视子目录，您知道如何使程序监视子目录吗？

watchfolder=New System.IO.FileSystemWatcher（）

/

warcher.IncludeSubdirectories=True

Hi！谢谢你这么快的回答，他们帮了我很大的忙，现在我的程序正按我所希望的那样工作！感谢Proputix和MPElletier的回答！祝你今天愉快！：）