Backgroundworker 不开始复制
Backgroundworker not starting copy
我是 VB.NET 的新手，正在开发一个应用程序，读取文本文件的内容并将其中的路径用于 file/folder 副本。我是 运行 通过 backgroundworker 复制的，它似乎不带 line 字符串。为了排除故障，我在行读取逻辑下放置了一个 MessageBox.Show(line) 以查看它是否正在读取路径。它不是，直接跳到我的 BackgroundWorker1_RunWorkerCompleted 子。
谁能看出我哪里错了？！
Private Sub BackgroundWorker1_DoWork(ByVal sender As System.Object, ByVal e As ComponentModel.DoWorkEventArgs, Optional ByVal Overwrite As Boolean = True) Handles BackgroundWorker1.DoWork
Dim deststring As String
' Open config.txt with the Using statement.
Using r As StreamReader = New StreamReader(Application.StartupPath + "\CONFIG.txt")
Dim line As String
' Read first line.
line = r.ReadLine
' Loop over each line in file, While list is Not Nothing.
Do While (Not line Is Nothing)
' Read line and filter based on logic
If line.StartsWith("*") Then
r.ReadLine()
ElseIf line.Contains(Destpath) Then
r.ReadLine()
ElseIf line.Equals("%USERPROFILE%\Desktop") Then
line = desktoppath
ElseIf line.Equals("%USERPROFILE%\Downloads") Then
line = downloadsPath
ElseIf line.Equals("%USERPROFILE%\Contacts") Then
line = contactspath
ElseIf line.Equals("%USERPROFILE%\Documents") Then
line = documentspath
ElseIf line.Equals("%USERPROFILE%\Favorites") Then
line = favoritespath
ElseIf line.Equals("%USERPROFILE%\Links") Then
line = linkspath
ElseIf line.Equals("%USERPROFILE%\Music") Then
line = Musicpath
ElseIf line.Equals("%USERPROFILE%\Pictures") Then
line = picturespath
ElseIf line.Equals("%USERPROFILE%\SavedGames") Then
line = savedgamespath
ElseIf line.Equals("%USERPROFILE%\SavedSearches") Then
line = savedsearchespath
ElseIf line.Equals("%USERPROFILE%\Videos") Then
line = videospath
ElseIf line.Contains("%USERNAME%") Then
line = line.Replace("%USERNAME%", Username)
Else
Console.Writeline(line)
'Read line and create a full path for the destination
Dim SubPath As String = line.Split("\").Last
Dim FullDestPath As String = Destpath & "\" & SubPath
Console.Writeline(FullDestPath)
If Not System.IO.Directory.Exists(FullDestPath) Then
System.IO.Directory.CreateDirectory(FullDestPath)
End If
'Get directory info's
Dim SourceDir As DirectoryInfo = New DirectoryInfo(line)
Dim DestDir As DirectoryInfo = New DirectoryInfo(FullDestPath)
Dim ChildFile As FileInfo
'Loop through each file in the SourceDir
For Each ChildFile In SourceDir.GetFiles()
'Display file being copied
SetLabelText_ThreadSafe(Me.lblStatus, "Copying: " & line & "\" & ChildFile.Name & "")
'Do the copy
ChildFile.CopyTo(Path.Combine(DestDir.FullName, ChildFile.Name), True)
deststring = DestDir.ToString & "\" & ChildFile.Name
Dim sourcedirstring As String
sourcedirstring = SourceDir.ToString & "\" & ChildFile.Name
'Open Stream
Dim CopyStream As New FileStream(sourcedirstring, FileMode.Open, FileAccess.Read)
Dim NewStream As New FileStream(deststring, FileMode.CreateNew)
Dim Buffer(100000) As Byte
Dim BytesRead As Integer
'Try loop for each file
Try
Do
BytesRead = CopyStream.Read(Buffer, 0, Buffer.Length)
NewStream.Write(Buffer, 0, BytesRead)
PercentComplete = (NewStream.Length / CopyStream.Length * 100)
PercentComplete = Decimal.Round((PercentComplete), 2)
If PercentComplete > 100 Then
PercentComplete = "0"
End If
'if the file count is only 1 file then make both progress bars the same so that the current file and total are the same
If filecount = 1 Then
percentage = ((NewStream.Length + filetotalsofarcopied) / Overallsize.ToString * 100)
percentage = Decimal.Round((percentage), 2)
If percentage > 100 Then
percentage = 0
End If
SetLabelText_ThreadSafe(Me.lblTotalProgress, "" & percentage & "%")
Else
Timer6.Start()
percentage2 = ((NewStream.Length + filetotalsofarcopied) / Overallsize.ToString * 100)
percentage2 = Decimal.Round((percentage2), 2)
If percentage2 > 100 Then
percentage2 = 0
End If
SetLabelText_ThreadSafe(Me.lblTotalProgress, "" & percentage2 & "%")
End If
SetLabelText_ThreadSafe(Me.lblCurrentFileProgress, "" & PercentComplete & "%")
Dim time As Long = Label22.Text
'Calculate copy speed
Dim kbps As Double = (NewStream.Length + filetotalsofarcopied) / (time * 1024)
If kbps < 1024 Then
SetLabelText_ThreadSafe(Me.lblCopy, String.Format("Copy Speed: {0:0.00} KB/s", kbps))
Else
SetLabelText_ThreadSafe(Me.lblCopy, String.Format("Copy Speed: {0:0.00} MB/s", kbps / 1024))
End If
Loop Until BytesRead = 0 And PercentComplete = 100
Catch ex As Exception
Finally
CopyStream.Dispose()
NewStream.Dispose()
End Try
'File counter
int3 = int3 + 1
'Calculate data being moved for eta to completion
Dim filetotalbytes As Double = ChildFile.Length
filetotalsofarcopied = filetotalbytes + filetotalsofarcopied
'Check for pending cancel
If BackgroundWorker1.CancellationPending = True Then
BackgroundWorker1.CancelAsync()
Exit Sub
End If
Next
'Loop through Sub directories of SourceDir
Dim SubDir As DirectoryInfo
For Each SubDir In SourceDir.GetDirectories()
CopyDirectory(SubDir.FullName, Path.Combine(DestDir.FullName, SubDir.Name), Overwrite)
Next
End If
' Read in the next line.
line = r.ReadLine
Loop
End Using
End Sub
更新：包含的 .text 文件内容：
***DESTINATION***
D:\Test
***Sources***
%USERPROFILE%\Downloads
%USERPROFILE%\Favorites
D:\User Data\Adam\Documents\Test
您应该删除前两个 If 中对 ReadLine 的调用，并将它们替换为 Continue Do 关键字。
一般来说，最好在代码中只调用一次 ReadLine。
例如，您可以使用 StreamReader.Peek 方法检查流结束。
最后应该在 %USERNAME% 检查后关闭 If 块
' removed
' line = r.ReadLine()
Dim line As String
Do While r.Peek <> -1
line = r.ReadLine()
Console.Writeline(line)
If line.StartsWith("*") Then
' Not significant, skip to the next line
Continue Do
ElseIf line.Contains(Destpath) Then
' Not significant, skip to the next line
Continue Do
ElseIf line.Equals("%USERPROFILE%\Desktop") Then
line = desktoppath
ElseIf line.Equals("%USERPROFILE%\Downloads") Then
line = downloadsPath
ElseIf line.Equals("%USERPROFILE%\Contacts") Then
line = contactspath
ElseIf line.Equals("%USERPROFILE%\Documents") Then
line = documentspath
ElseIf line.Equals("%USERPROFILE%\Favorites") Then
line = favoritespath
ElseIf line.Equals("%USERPROFILE%\Links") Then
line = linkspath
ElseIf line.Equals("%USERPROFILE%\Music") Then
line = Musicpath
ElseIf line.Equals("%USERPROFILE%\Pictures") Then
line = picturespath
ElseIf line.Equals("%USERPROFILE%\SavedGames") Then
line = savedgamespath
ElseIf line.Equals("%USERPROFILE%\SavedSearches") Then
line = savedsearchespath
ElseIf line.Equals("%USERPROFILE%\Videos") Then
line = videospath
ElseIf line.Contains("%USERNAME%") Then
line = line.Replace("%USERNAME%", Username)
End If
' Now your line variable should be always correct and
' you can execute your copying logic
......
line = r.ReadLine
Loop
我是 VB.NET 的新手，正在开发一个应用程序，读取文本文件的内容并将其中的路径用于 file/folder 副本。我是 运行 通过 backgroundworker 复制的，它似乎不带 line 字符串。为了排除故障，我在行读取逻辑下放置了一个 MessageBox.Show(line) 以查看它是否正在读取路径。它不是，直接跳到我的 BackgroundWorker1_RunWorkerCompleted 子。
谁能看出我哪里错了？！
Private Sub BackgroundWorker1_DoWork(ByVal sender As System.Object, ByVal e As ComponentModel.DoWorkEventArgs, Optional ByVal Overwrite As Boolean = True) Handles BackgroundWorker1.DoWork
Dim deststring As String
' Open config.txt with the Using statement.
Using r As StreamReader = New StreamReader(Application.StartupPath + "\CONFIG.txt")
Dim line As String
' Read first line.
line = r.ReadLine
' Loop over each line in file, While list is Not Nothing.
Do While (Not line Is Nothing)
' Read line and filter based on logic
If line.StartsWith("*") Then
r.ReadLine()
ElseIf line.Contains(Destpath) Then
r.ReadLine()
ElseIf line.Equals("%USERPROFILE%\Desktop") Then
line = desktoppath
ElseIf line.Equals("%USERPROFILE%\Downloads") Then
line = downloadsPath
ElseIf line.Equals("%USERPROFILE%\Contacts") Then
line = contactspath
ElseIf line.Equals("%USERPROFILE%\Documents") Then
line = documentspath
ElseIf line.Equals("%USERPROFILE%\Favorites") Then
line = favoritespath
ElseIf line.Equals("%USERPROFILE%\Links") Then
line = linkspath
ElseIf line.Equals("%USERPROFILE%\Music") Then
line = Musicpath
ElseIf line.Equals("%USERPROFILE%\Pictures") Then
line = picturespath
ElseIf line.Equals("%USERPROFILE%\SavedGames") Then
line = savedgamespath
ElseIf line.Equals("%USERPROFILE%\SavedSearches") Then
line = savedsearchespath
ElseIf line.Equals("%USERPROFILE%\Videos") Then
line = videospath
ElseIf line.Contains("%USERNAME%") Then
line = line.Replace("%USERNAME%", Username)
Else
Console.Writeline(line)
'Read line and create a full path for the destination
Dim SubPath As String = line.Split("\").Last
Dim FullDestPath As String = Destpath & "\" & SubPath
Console.Writeline(FullDestPath)
If Not System.IO.Directory.Exists(FullDestPath) Then
System.IO.Directory.CreateDirectory(FullDestPath)
End If
'Get directory info's
Dim SourceDir As DirectoryInfo = New DirectoryInfo(line)
Dim DestDir As DirectoryInfo = New DirectoryInfo(FullDestPath)
Dim ChildFile As FileInfo
'Loop through each file in the SourceDir
For Each ChildFile In SourceDir.GetFiles()
'Display file being copied
SetLabelText_ThreadSafe(Me.lblStatus, "Copying: " & line & "\" & ChildFile.Name & "")
'Do the copy
ChildFile.CopyTo(Path.Combine(DestDir.FullName, ChildFile.Name), True)
deststring = DestDir.ToString & "\" & ChildFile.Name
Dim sourcedirstring As String
sourcedirstring = SourceDir.ToString & "\" & ChildFile.Name
'Open Stream
Dim CopyStream As New FileStream(sourcedirstring, FileMode.Open, FileAccess.Read)
Dim NewStream As New FileStream(deststring, FileMode.CreateNew)
Dim Buffer(100000) As Byte
Dim BytesRead As Integer
'Try loop for each file
Try
Do
BytesRead = CopyStream.Read(Buffer, 0, Buffer.Length)
NewStream.Write(Buffer, 0, BytesRead)
PercentComplete = (NewStream.Length / CopyStream.Length * 100)
PercentComplete = Decimal.Round((PercentComplete), 2)
If PercentComplete > 100 Then
PercentComplete = "0"
End If
'if the file count is only 1 file then make both progress bars the same so that the current file and total are the same
If filecount = 1 Then
percentage = ((NewStream.Length + filetotalsofarcopied) / Overallsize.ToString * 100)
percentage = Decimal.Round((percentage), 2)
If percentage > 100 Then
percentage = 0
End If
SetLabelText_ThreadSafe(Me.lblTotalProgress, "" & percentage & "%")
Else
Timer6.Start()
percentage2 = ((NewStream.Length + filetotalsofarcopied) / Overallsize.ToString * 100)
percentage2 = Decimal.Round((percentage2), 2)
If percentage2 > 100 Then
percentage2 = 0
End If
SetLabelText_ThreadSafe(Me.lblTotalProgress, "" & percentage2 & "%")
End If
SetLabelText_ThreadSafe(Me.lblCurrentFileProgress, "" & PercentComplete & "%")
Dim time As Long = Label22.Text
'Calculate copy speed
Dim kbps As Double = (NewStream.Length + filetotalsofarcopied) / (time * 1024)
If kbps < 1024 Then
SetLabelText_ThreadSafe(Me.lblCopy, String.Format("Copy Speed: {0:0.00} KB/s", kbps))
Else
SetLabelText_ThreadSafe(Me.lblCopy, String.Format("Copy Speed: {0:0.00} MB/s", kbps / 1024))
End If
Loop Until BytesRead = 0 And PercentComplete = 100
Catch ex As Exception
Finally
CopyStream.Dispose()
NewStream.Dispose()
End Try
'File counter
int3 = int3 + 1
'Calculate data being moved for eta to completion
Dim filetotalbytes As Double = ChildFile.Length
filetotalsofarcopied = filetotalbytes + filetotalsofarcopied
'Check for pending cancel
If BackgroundWorker1.CancellationPending = True Then
BackgroundWorker1.CancelAsync()
Exit Sub
End If
Next
'Loop through Sub directories of SourceDir
Dim SubDir As DirectoryInfo
For Each SubDir In SourceDir.GetDirectories()
CopyDirectory(SubDir.FullName, Path.Combine(DestDir.FullName, SubDir.Name), Overwrite)
Next
End If
' Read in the next line.
line = r.ReadLine
Loop
End Using
End Sub
更新：包含的 .text 文件内容：
***DESTINATION***
D:\Test
***Sources***
%USERPROFILE%\Downloads
%USERPROFILE%\Favorites
D:\User Data\Adam\Documents\Test
您应该删除前两个 If 中对 ReadLine 的调用，并将它们替换为 Continue Do 关键字。
一般来说，最好在代码中只调用一次 ReadLine。
例如，您可以使用 StreamReader.Peek 方法检查流结束。
最后应该在 %USERNAME% 检查后关闭 If 块
' removed
' line = r.ReadLine()
Dim line As String
Do While r.Peek <> -1
line = r.ReadLine()
Console.Writeline(line)
If line.StartsWith("*") Then
' Not significant, skip to the next line
Continue Do
ElseIf line.Contains(Destpath) Then
' Not significant, skip to the next line
Continue Do
ElseIf line.Equals("%USERPROFILE%\Desktop") Then
line = desktoppath
ElseIf line.Equals("%USERPROFILE%\Downloads") Then
line = downloadsPath
ElseIf line.Equals("%USERPROFILE%\Contacts") Then
line = contactspath
ElseIf line.Equals("%USERPROFILE%\Documents") Then
line = documentspath
ElseIf line.Equals("%USERPROFILE%\Favorites") Then
line = favoritespath
ElseIf line.Equals("%USERPROFILE%\Links") Then
line = linkspath
ElseIf line.Equals("%USERPROFILE%\Music") Then
line = Musicpath
ElseIf line.Equals("%USERPROFILE%\Pictures") Then
line = picturespath
ElseIf line.Equals("%USERPROFILE%\SavedGames") Then
line = savedgamespath
ElseIf line.Equals("%USERPROFILE%\SavedSearches") Then
line = savedsearchespath
ElseIf line.Equals("%USERPROFILE%\Videos") Then
line = videospath
ElseIf line.Contains("%USERNAME%") Then
line = line.Replace("%USERNAME%", Username)
End If
' Now your line variable should be always correct and
' you can execute your copying logic
......
line = r.ReadLine
Loop