FTP上传破坏文件 [英] FTP upload corrupting files

问题描述

程序我正在处理Excel文件上传时损坏的文件。
本地计算机上的文件可以，但在远程计算机上，文件在Excel中打开时会损坏。 Excel能够修复文件，但是我不想避免这个问题。

到目前为止，我似乎没有任何图像文件问题。

 公共功能UploadFile（BYVAL用户作为字符串，BYVAL OFILE作为FileInfo的）为布尔
尺寸ftpRequest作为的FtpWebRequest 
尺寸ftpResponse作为FtpWebResponse 
尝试
 FtpCheckAndCreateDir（用户）
 
 ftpRequest = CTYPE（FtpWebRequest.Create（基地+用户+ / + oFile.Name）的FtpWebRequest）
 ftpRequest.Method = WebRequestMethods。 Ftp.UploadFile 
 ftpRequest.Proxy =什么
 ftpRequest.UseBinary =真
 ftpRequest.Credentials =中房 '新的NetworkCredential（...）
 ftpRequest.KeepAlive =保持活动' 假
 ftpRequest.EnableSsl = UseSSL'false 
如果UseSSL Then ServicePointManager.ServerCertificateValidationCallback = New RemoteCertificateValidationCallback（AddressOf ValidateServerCertificate）
 Dim fileContents（oFile.Length）As Byte 
使用fr作为FileStream = oFile.OpenRead 
 fr.Read（fileContents，0，Convert.ToInt32（oFile.Length））
 End使用
使用写入器作为流= ftpRequest.GetRequestStream 
 writer.Write（fileContents，0，fileContents.Length）
结束使用
 ftpResponse = CTYPE（ftpRequest.GetResponse，FtpWebResponse）
 ftpResponse.Close（）
 ftpRequest = Nothing 
返回True 
 Catch ex As WebException 
返回False 
结束尝试
 End Function 
  

编辑：

所以我拿了一个文件并通过coffeecup免费的ftp上传，下载了它，打开罚款。

我用我的程序来上传文件，然后用咖啡杯下载它，当我尝试在Excel中打开它时，它已经损坏。

我用HxD来比较这些文件，并且它回来后显示一条消息：所选的文件s是一样的。不过，文件大小是不同的！当我在两个文件上运行校验和时，它们会返回不同的值。

我不确定如何解决此问题或者我可以研究找到答案。

如果需要，我可以提供这些文件。 所以，经过大量的搜索和查找之后，我发现了这个答案： C＃ - 上传到服务器后文件已损坏

我可以使用它来获取文件上传而不被破坏。

使用旧零件的最终ftp函数注释掉，以便更容易看到更改：

 公共功能UploadFile（BYVAL用户作为字符串，BYVAL OFILE作为FileInfo的）为布尔
尺寸ftpRequest作为的FtpWebRequest 
尺寸ftpResponse作为FtpWebResponse 
尝试
 FtpCheckAndCreateDir（用户）
 
 ftpRequest = CType（FtpWebRequest.Create（Base + User +/+ oFile.Name），FtpWebRequest）
 ftpRequest.Method = WebRequestMethods.Ftp.UploadFile 
 ftpRequest.Proxy = Nothing 
 ftpRequest .UseBinary =真
 ftpRequest.Credentials =中房
 ftpRequest.KeepAlive =保持活动
 ftpRequest.EnableSsl = UseSSL 
，如果useSsl然后ServicePointManager.ServerCertificateValidationCallback =新RemoteCertificateValidationCallback（AddressOf ValidateServerCertificate）
 Dim fileContents（oFile.Length）As Byte 
 
使用fr作为FileStream = oFile.OpenRead 
使用writer作为Stream = ftpRequest.GetRequestStream 
 fr.CopyTo（writer）'这是重要的部分。 
'writer.Write（fileContents，0，fileContents.Length）
结束使用
'fr.Read（fileContents，0，Convert.ToInt32（oFile.Length））
 End使用
'使用writer作为Stream = ftpRequest.GetRequestStream 
'writer.Write（fileContents，0，fileContents.Length）
'End使用
 ftpResponse = CType（ftpRequest.GetResponse， FtpWebResponse）
 ftpResponse.Close（）
 ftpRequest = Nothing 
返回True 
 Catch ex As WebException 
返回False 
结束尝试
 End Function 
  

Program I am working on corrupts Excel files when it uploads them. The file is ok on the local computer, but on the remote computer the file says corrupted when opening in Excel. Excel is able to repair the file, but I wan't to avoid the problem.
I don't seem to have any problems with image files so far.

Public Function UploadFile(ByVal User As String, ByVal oFile As FileInfo) As Boolean
    Dim ftpRequest As FtpWebRequest
    Dim ftpResponse As FtpWebResponse
    Try
        FtpCheckAndCreateDir(User)

        ftpRequest = CType(FtpWebRequest.Create(Base + User + "/" + oFile.Name), FtpWebRequest)
        ftpRequest.Method = WebRequestMethods.Ftp.UploadFile
        ftpRequest.Proxy = Nothing
        ftpRequest.UseBinary = True
        ftpRequest.Credentials = Cred ' New NetworkCredential(...)
        ftpRequest.KeepAlive = KeepAlive ' false
        ftpRequest.EnableSsl = UseSSL ' false
        If UseSSL Then ServicePointManager.ServerCertificateValidationCallback = New RemoteCertificateValidationCallback(AddressOf ValidateServerCertificate)
        Dim fileContents(oFile.Length) As Byte
        Using fr As FileStream = oFile.OpenRead
            fr.Read(fileContents, 0, Convert.ToInt32(oFile.Length))
        End Using
        Using writer As Stream = ftpRequest.GetRequestStream
            writer.Write(fileContents, 0, fileContents.Length)
        End Using
        ftpResponse = CType(ftpRequest.GetResponse, FtpWebResponse)
        ftpResponse.Close()
        ftpRequest = Nothing
        Return True
    Catch ex As WebException
        Return False
    End Try
End Function

EDIT:
So I took a file and uploaded it through coffeecup free ftp, downloaded it, and it opened fine.
I used my program to upload the file, and then downloaded it with with coffeecup and it came up as damaged when I tried to open it in excel.
I used HxD to compare the files, and it came back with a message saying: "The chosen files are identical. The files sizes are different, though!" and when I run a checksum on both files they come back with different values.

I'm not really sure how to troubleshoot this or what I can research to find the answer.
I can provide the files if needed.

解决方案

So, after a lot of searching and looking, I found this answer: C# - File is corrupt after uploaded to server

which I was able to use to get a file to upload without being corrupted.

The final ftp function with old parts commented out to make it easier to see the changes:

Public Function UploadFile(ByVal User As String, ByVal oFile As FileInfo) As Boolean
    Dim ftpRequest As FtpWebRequest
    Dim ftpResponse As FtpWebResponse
    Try
        FtpCheckAndCreateDir(User)

        ftpRequest = CType(FtpWebRequest.Create(Base + User + "/" + oFile.Name), FtpWebRequest)
        ftpRequest.Method = WebRequestMethods.Ftp.UploadFile
        ftpRequest.Proxy = Nothing
        ftpRequest.UseBinary = True
        ftpRequest.Credentials = Cred
        ftpRequest.KeepAlive = KeepAlive
        ftpRequest.EnableSsl = UseSSL
        If UseSSL Then ServicePointManager.ServerCertificateValidationCallback = New RemoteCertificateValidationCallback(AddressOf ValidateServerCertificate)
        Dim fileContents(oFile.Length) As Byte

        Using fr As FileStream = oFile.OpenRead
            Using writer As Stream = ftpRequest.GetRequestStream
                fr.CopyTo(writer) ' This is the important part.
                'writer.Write(fileContents, 0, fileContents.Length)
            End Using
            'fr.Read(fileContents, 0, Convert.ToInt32(oFile.Length))
        End Using
        'Using writer As Stream = ftpRequest.GetRequestStream
        '    writer.Write(fileContents, 0, fileContents.Length)
        'End Using
        ftpResponse = CType(ftpRequest.GetResponse, FtpWebResponse)
        ftpResponse.Close()
        ftpRequest = Nothing
        Return True
    Catch ex As WebException
        Return False
    End Try
End Function

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