FtpWebRequest：创建嵌套目录（本地与远程）答案

【问题标题】：FtpWebRequest: create nested directories (local vs remote)FtpWebRequest：创建嵌套目录（本地与远程）
【发布时间】：2016-05-07 12:23:49
【问题描述】：

目标：

我想在上传文件之前确保 FTP 路径存在，如果不存在 ==> 创建它。

我正在使用的代码：

Dim ftpPath As String = "ftp://----------/ParentDir/SubFolder1/SubFolder2"
If Not FTPDirExists(ftpPath) Then
    CreateFTPDir(ftpPath)
End If

CreateFTPDir 在哪里：

Private Sub CreateFTPDir(DirPath As String)
    Dim request As FtpWebRequest = FtpWebRequest.Create(DirPath)
    request.Credentials = New NetworkCredential("UserName", "Password")
    request.Method = WebRequestMethods.Ftp.MakeDirectory
    request.Proxy = Nothing
    request.KeepAlive = True
    Try
        Dim resp As FtpWebResponse = request.GetResponse()
    Catch ex As Exception
        Console.WriteLine(ex.Message)
    End Try
End Sub

现在，当我在本地 FTP 服务器（使用 FileZilla 创建）上测试此代码时，无论嵌套目录的数量如何，它都会创建路径。但是当我在实际 ( remote) FTP 服务器，它会抛出以下异常：The remote server returned an error: (550) File unavailable 如果要创建的目录不止一个。

我的问题是为什么本地服务器不会出现这个问题？我必须在远程服务器上分别创建每个 nested 目录吗？

附加信息 + 第二个问题：

这是我正在使用的FTPDirExists 函数（经过大量搜索后我能想到的最好的）：

Private Function FTPDirExists(DirPath As String) As Boolean
    DirPath &= If(DirPath.EndsWith("/"), "", "/")
    Dim request As FtpWebRequest = FtpWebRequest.Create(DirPath)
    request.Credentials = New NetworkCredential("UserName", "Password")
    request.Method = WebRequestMethods.Ftp.ListDirectoryDetails
    request.Proxy = Nothing
    request.KeepAlive = True
    Try
        Using resp As FtpWebResponse = request.GetResponse()
            Return True
        End Using
    Catch ex As WebException
        Dim resp As FtpWebResponse = DirectCast(ex.Response, FtpWebResponse)
        If resp.StatusCode = FtpStatusCode.ActionNotTakenFileUnavailable Then
            Return False ' ==> Unfortunately will return false for other reasons (like no permission).
        Else
            Return False ' ==> Don't bother about this.
        End If
    End Try
End Function

正如我在上面的评论中提到的那样，它不是 100% 准确的，所以如果您有更准确的方法，请告诉我。

【问题讨论】：

标签： .net vb.net ftpwebrequest

【解决方案1】：

我决定使用另一个函数来分别创建路径的每个文件夹：

Public Shared Sub CreatePath(RootPath As String, PathToCreate As String, Cred As NetworkCredential)
    Dim request As FtpWebRequest
    Dim subDirs As String() = PathToCreate.Split("/"c)
    Dim currentDir As String = If(RootPath.EndsWith("/"), RootPath.Substring(0, RootPath.Length - 1), RootPath)
    For Each subDir As String In subDirs
        currentDir &= "/" & subDir

        request = DirectCast(FtpWebRequest.Create(currentDir), FtpWebRequest)
        request.Credentials = Cred
        request.Method = WebRequestMethods.Ftp.MakeDirectory
        request.Proxy = Nothing
        Try
            Dim response As FtpWebResponse = DirectCast(request.GetResponse(), FtpWebResponse)
            response.Close()
        Catch ex As Exception

        End Try
    Next
End Sub

【讨论】：