Connecting ftp server with credentials

问题:

I'm writing a program that uses an ftp server with credentials. I'm trying to retrieve the directory list from the server but when I get to the line:

string line = reader.ReadLine();

the string that I get contains only : "Can't open \"host:/lib1\"."

If I try to get another line, the next exception is thrown: The remote server returned an error: (550) File unavailable (e.g., file not found, no access).

I know for sure (using another ftp application) that 'lib1' directory exists on the ftp server and my credentials (username and password) are correct.

Here is my code:

 public class FTPClient
{
    public string UserName { get; set; }
    public string Password { get; set; }
    public string IpAddress { get; set; }
    public int Port { get; set; }

    public FTPClient(string _userName, string _password, string _address, int _port)
    {
        UserName = _userName;
        Password = _password;
        IpAddress = _address;
        Port = _port;
    }

    public void GetDirectoriesList(string _path)
    {           
        FtpWebRequest request = (FtpWebRequest)WebRequest.Create(new Uri("ftp://" + 
        IpAddress + _path));
        request.UseBinary = true;
        request.Method = WebRequestMethods.Ftp.ListDirectory;
        request.Credentials = new NetworkCredential(UserName, Password);

        FtpWebResponse response = (FtpWebResponse)request.GetResponse();
        Stream responseStream = response.GetResponseStream();
        StreamReader reader = new StreamReader(responseStream);

        string line = reader.ReadLine();
        while (line!=null)
        {
            ... //do something with line
            line = reader.ReadLine();
        }
        ...
        reader.Close();
        response.Close();


    }

And I use it as follows:

FTPClient ftpClient = new FTPClient("user1", "pass1", "192.168.2.110", 21);

        string dirList = ftpClient.GetDirectoriesList("/lib1");

Can anyone spot the problem?

回答1:

My solution:

public string[] GetDirectory()
{
    StringBuilder result = new StringBuilder();
    FtpWebRequest requestDir = (FtpWebRequest)WebRequest.Create("ftp://urserverip/");
    requestDir.Method = WebRequestMethods.Ftp.ListDirectory;
    requestDir.Credentials = new NetworkCredential("username", "password");
    FtpWebResponse responseDir = (FtpWebResponse)requestDir.GetResponse();
    StreamReader readerDir  = new StreamReader(responseDir.GetResponseStream());

    string line = readerDir.ReadLine();
    while (line != null)
    {
        result.Append(line);
        result.Append("\n");
        line = readerDir.ReadLine();
    }

    result.Remove(result.ToString().LastIndexOf('\n'), 1);
    responseDir.Close(); 
    return result.ToString().Split('\n');
}

回答2:

Some refinements to Abdul Waheed's answer:

• Added using blocks to clean up the FtpWebResponse and StreamReader objects;

• Reduced string manipulation:

  private static string[] GetDirectoryListing()
  {
      FtpWebRequest directoryListRequest = (FtpWebRequest)WebRequest.Create("ftp://urserverip/");
      directoryListRequest.Method = WebRequestMethods.Ftp.ListDirectory;
      directoryListRequest.Credentials = new NetworkCredential("username", "password");
  
      using (FtpWebResponse directoryListResponse = (FtpWebResponse)directoryListRequest.GetResponse())
      {
          using (StreamReader directoryListResponseReader = new StreamReader(directoryListResponse.GetResponseStream()))
          {
              string responseString = directoryListResponseReader.ReadToEnd();
              string[] results = responseString.Split(new string[] { "\r\n", "\n" }, StringSplitOptions.RemoveEmptyEntries);
              return results;
          }
      }
  }