c# ftp 上传到 Linux

Question

我正在尝试检查 FTP 服务器上是否存在目录。在您说“使用 ListDirectory”或“使用 PrintWorkingDirectory”之前，它们并不总是有效；例如，我测试了是否 ftp://webserver/Logs存在，并且都告诉我它确实存在，但实际上并不存在。所以我沿着将文件上传到目录的路线走下去，如果成功，那么目录就存在。

问题是，下面的方法不适用于运行 vsFTPd 2.0.7.2 的 GoDaddy 基于 CentOS 的服务器。适用于 IIS7.5 上的 Microsoft FTP 服务器。

因此，我使用 Wireshark 监控流量并使用 Filezilla 查看它在做什么，而我的应用程序无法使其正常工作。唯一的区别是 Filezilla 正在更改工作目录，因为我正在尝试使用它之前的路径上传文件。

我觉得它与上传到服务器的路径和 Linux 的解释有关，因为它的名称可能有点有趣...:-D 热烈欢迎任何想法？

应用代码

private bool DirectoryExists(string d)
{
    bool exists = true;
    try
    {
        string file = "directoryexists.test";
        string path = url + homepath + d + "/" + file;

        //Try to save to the directory
        req = (FtpWebRequest)WebRequest.Create(path);
        req.ConnectionGroupName = "conngroup1";
        req.Method = WebRequestMethods.Ftp.UploadFile;
        if (nc != null) req.Credentials = nc;
        if (cbSSL.Checked) req.EnableSsl = true;
        req.Timeout = 10000;

        byte[] fileContents = System.Text.Encoding.Unicode.GetBytes("SAFE TO DELETE");
        req.ContentLength = fileContents.Length;

        Stream s = req.GetRequestStream();
        s.Write(fileContents, 0, fileContents.Length);
        s.Close();

        //Delete file if successful
        req = (FtpWebRequest)WebRequest.Create(path);
        req.ConnectionGroupName = "conngroup1";
        req.Method = WebRequestMethods.Ftp.DeleteFile;
        if (nc != null) req.Credentials = nc;
        if (cbSSL.Checked) req.EnableSsl = true;
        req.Timeout = 10000;

        res = (FtpWebResponse)req.GetResponse();
        res.Close();
    }
    catch (WebException ex)
    {
        exists = false;
    }
    return exists;
}

通过 Wireshark 的 Filezilla 日志

Response: 230 Login successful.
Request: CWD /Home/test1
Response: 250 Directory successfully changed.
Request: TYPE I
Response: 200 Switching to Binary mode.
Request: PASV
Response: 227 Entering Passive Mode (216,69,186,142,71,209)
Request: LIST
Response: 150 Here comes the directory listing.
FTP Data: 78 bytes
Response: 226 Directory send OK.
Request: PASV
Response: 227 Entering Passive Mode (216,69,186,142,177,1)
Request: STOR directoryexists.txt
Response: 150 Ok to send data.
Response: 226 File receive OK.

通过 Wireshark 记录应用程序

Response: 230 Login successful.
Request: OPTS utf8 on
Response: 501 Option not understood.
Request: PWD
Response: 257 "/Home/"
Request: PWD
Response: 257 "/Home/"
Request: TYPE I
Response: 200 Switching to Binary mode.
Request: PASV
Response: 227 Entering Passive Mode (216,69,186,142,217,87)
Request: STOR test1/directoryexists.txt
Response: 553 Could not create file.

---

如果文件夹不存在，它会创建文件夹。

Response: 230 Login successful.
Request: PWD
Response: 257 "/Home/"
Request: PWD
Response: 257 "/Home/"
Request: TYPE I
Response: 200 Switching to Binary mode.
Request: PASV
Response: 227 Entering Passive Mode (216,69,186,142,220,60)
Request: STOR Logs/directoryexists.txt
Response: 553 Could not create file.
Request: PWD
Response: 257 "/Home/"
Request: MKD Logs
Response: 257 Create folder operation successful.
Request: TYPE I
Response: 200 Switching to Binary mode.
Request: PASV
Response: 227 Entering Passive Mode (216,69,186,142,255,245)
Request: STOR Logs/LogFiles/directoryexists.txt
Response: 553 Could not create file.
Request: PWD
Response: 257 "/Home/"
Request: MKD Logs/LogFiles
Response: 257 Create folder operation successful.

Answer 1

Linux 又咬人了...

解决方案是在路径名中设置一个双斜杠，这样当涉及到 STOR 时，它有一个前导斜杠......像这样:

string url = "ftp://website/";
string homepath = "/Home/";
string d = "test1";
string file = "directoryexists.test";

string path = url + homepath + d + "/" + file;

所以完整的路径看起来像ftp://website//Home/test1/directoryexists.test

req = (FtpWebRequest)WebRequest.Create("ftp://website//Home/test1/directoryexists.test"); 

这样 STOR 命令看起来像

STOR /Home/test1/directoryexists.test

您可以从 StatusDescription 中获取 Home 路径

req = (FtpWebRequest)WebRequest.Create(url);
req.Method = WebRequestMethods.Ftp.PrintWorkingDirectory;
if (nc != null) req.Credentials = nc;
if (cbSSL.Checked) req.EnableSsl = true;
req.Timeout = 10000;
res = (FtpWebResponse)req.GetResponse();

System.Text.RegularExpressions.Regex regexp = new System.Text.RegularExpressions.Regex("\\s\"([^\"]*)\"\\s");
homepath = regexp.Match(res.StatusDescription).Groups[1].Value;

res.Close();