为什么我的在线文本文件在VB.NET中下载是空白的？

在Visual Studio Community 2015中下载文本文件时遇到问题。它是我的OneDrive公用文件夹中的文本文件，包含我的应用程序的版本号（1.0.0.0）。我使用的下载链接在手动打开时工作得很好，但是当我的VB代码执行时，它确实正确地下载了文本文件，但是当我打开它时，该文件是空白的，我无法找出哪里出错了

在模块1中，我有一个用于下载的sub和一个用于随后读取文件的sub：

Module Module1

    ' Public variables

    Public tempPath As String = Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData) & "\Temp"

    Sub DownloadToTemp(filePath As String)
        ' Download a text file, ready to read contents

        If Not IO.Directory.Exists(tempPath & "\Temp") Then
            IO.Directory.CreateDirectory(tempPath & "\Temp")
        End If

        Try
            My.Computer.Network.DownloadFile _
                (address:=filePath,
                destinationFileName:=tempPath & "\TempText.txt",
                userName:=String.Empty,
                password:=String.Empty,
                showUI:=False,
                connectionTimeout:=10000,
                overwrite:=True)

        Catch ex As Exception
            MsgBox("Can't read file" & vbCrLf & ex.Message)
        End Try

    End Sub

    Sub ReadFile()

        Dim fStream As New IO.FileStream(tempPath & "\TempText.txt", IO.FileMode.Open)
        Dim sReader As New System.IO.StreamReader(fStream)
        Dim sArray As String() = Nothing
        Dim index As Integer = 0

        Do While sReader.Peek >= 0
            ReDim Preserve sArray(index)
            sArray(index) = sReader.ReadLine
            index += 1
        Loop

        fStream.Close()
        sReader.Close()

        ' Test
        Dim fileContents As String = Nothing
        If sArray Is Nothing Then
            MsgBox("No Data Found")
            Exit Sub
        End If
        For index = 0 To UBound(sArray)
            fileContents = fileContents & sArray(index) & vbCrLf
        Next

        MessageBox.Show(fileContents)

    End Sub

End Module

它们是从主代码调用的：

    Private Sub frmSplash_Load(sender As Object, e As EventArgs) Handles MyBase.Load

    lblVersion.Text = "v" & Application.ProductVersion

    ' Check available version online

    Call DownloadToTemp("https://onedrive.live.com/download?resid=DE2331D1649390C1!16974&authkey=!AH2cr1S1SHs9Epk&ithint=file%2ctxt")
    Call ReadFile()

End Sub

---

因此，一切似乎都是正确的和工作的，没有错误或异常，但我的VB代码下载的文件是空白的，但手动单击代码中的下载链接下载它，内容保持不变。有人知道为什么会发生这种情况吗？

代码将下载该位置的任何内容，但该链接似乎会将您重定向到另一个位置。它下载从链接得到的响应，因为那里什么都没有，所以它什么都没有

您需要直接链接到该文件才能正常工作。请尝试以下方法：

DownloadToTemp("https://gwhcha-dm2306.files.1drv.com/y4mwlpYyvyCFDPp3NyPM6WqOz8-Ocfn-W0_4RbdQBtNMATYn2jNgWMRgpl_gXdTBteipIevz07_oUjCkeNoJGUxNO9jC9IdXz60NNEvzx2cU9fYJU_oRgqBFyA8KkBs8VGc8gDbs2xz7d3FyFnkgRfq77A2guoosQkO4pVMDiEYRoJRCWOtQk2etsMXyT8nSEnPoGV6ZG0JWc6qt55Mhi_zeA/Hotshot_Version.txt?download&psid=1")

此外，您不需要使用。它的存在只是为了向后兼容VB6和旧版本

---

编辑：

Try
    DownloadFileWithRedirect("https://onedrive.live.com/download?resid=DE2331D1649390C1!16974&authkey=!AH2cr1S1SHs9Epk&ithint=file%2ctxt", Path.Combine(tempPath, "TempText.txt"))
Catch ex As Exception
    MessageBox.Show("An error occurred:" & Environment.NewLine & ex.Message, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error)
End Try

下面是一个使用下载文件的示例。通过设置其和属性，您可以在尝试下载文件之前对其进行重定向

''' <summary>
''' Downloads a file from an URL and allows the page to redirect you.
''' </summary>
''' <param name="Url">The URL to the file to download.</param>
''' <param name="TargetPath">The path and file name to download the file to.</param>
''' <param name="AllowedRedirections">The maximum allowed amount of redirections (default = 32).</param>
''' <param name="DownloadBufferSize">The amount of bytes of the download buffer (default = 4096 = 4 KB).</param>
''' <remarks></remarks>
Private Sub DownloadFileWithRedirect(ByVal Url As String, _
                                     ByVal TargetPath As String, _
                                     Optional ByVal AllowedRedirections As Integer = 32, _
                                     Optional ByVal DownloadBufferSize As Integer = 4096)
    'Create the request.
    Dim Request As HttpWebRequest = DirectCast(WebRequest.Create(Url), HttpWebRequest)
    Request.Timeout = 10000 '10 second timeout.
    Request.MaximumAutomaticRedirections = AllowedRedirections
    Request.AllowAutoRedirect = True

    'Get the response from the server.
    Using Response As HttpWebResponse = DirectCast(Request.GetResponse(), HttpWebResponse)
        'Get the stream to read the response.
        Using ResponseStream As Stream = Response.GetResponseStream()

            'Declare a download buffer.
            Dim Buffer() As Byte = New Byte(DownloadBufferSize - 1) {}
            Dim ReadBytes As Integer = 0

            'Create the target file and open a file stream to it.
            Using TargetFileStream As New FileStream(TargetPath, FileMode.Create, FileAccess.Write, FileShare.None)

                'Start reading into the buffer.
                ReadBytes = ResponseStream.Read(Buffer, 0, Buffer.Length)

                'Loop while there's something to read.
                While ReadBytes > 0
                    'Write the read bytes to the file.
                    TargetFileStream.Write(Buffer, 0, ReadBytes)

                    'Read more into the buffer.
                    ReadBytes = ResponseStream.Read(Buffer, 0, Buffer.Length)
                End While

            End Using

        End Using
    End Using
End Sub

---

杰出的很好，谢谢你。你能告诉我你是如何获得直接链接的吗？有转换重定向的公式吗？@JasonVB：我知道了，因为iPhone上的Safari web浏览器只会显示纯文本文件的内容，而不会询问您想对其做什么。因此，我不得不从标题栏复制直接链接还有其他方法可以获得直接链接，给我几分钟，我应该可以找到一些东西。@JasonVB:显然，

HttpWebRequest

类可以配置为允许重定向。看这个：（它是C语言的，但是可以用在线转换器轻松转换）。太棒了。非常感谢。@JasonVB：很高兴我能帮忙！如果你给我大约20分钟的时间，我也可以用代码更新我的答案。@VisualIncent令人印象深刻。我再次试图找到一种直接下载链接的方法，但这似乎是微软有意避免的。我肯定会使用HttpWebRequest类代码来允许重定向。再次感谢！很高兴我能帮忙！不过，我看到了对我答案的评论，所以没有必要重复发帖