在C#中，可以使用FtpWebRequest類來進行FTP操作，包括目錄操作。以下是一個示例代碼，演示如何在FTPS中進行目錄操作：

using System;
using System.Net;

class FtpDirectory
{
    public static void ListDirectory(string ftpAddress, string username, string password)
    {
        FtpWebRequest request = (FtpWebRequest)WebRequest.Create(ftpAddress);
        request.Credentials = new NetworkCredential(username, password);
        request.Method = WebRequestMethods.Ftp.ListDirectory;

        FtpWebResponse response = (FtpWebResponse)request.GetResponse();
        Console.WriteLine("Directory List:");
        Console.WriteLine();

        using (var reader = new System.IO.StreamReader(response.GetResponseStream()))
        {
            while (!reader.EndOfStream)
            {
                Console.WriteLine(reader.ReadLine());
            }
        }

        response.Close();
    }

    public static void CreateDirectory(string ftpAddress, string username, string password, string newDirectoryName)
    {
        FtpWebRequest request = (FtpWebRequest)WebRequest.Create(ftpAddress + "/" + newDirectoryName);
        request.Credentials = new NetworkCredential(username, password);
        request.Method = WebRequestMethods.Ftp.MakeDirectory;

        FtpWebResponse response = (FtpWebResponse)request.GetResponse();
        Console.WriteLine("Directory created successfully.");
        response.Close();
    }

    public static void DeleteDirectory(string ftpAddress, string username, string password, string directoryName)
    {
        FtpWebRequest request = (FtpWebRequest)WebRequest.Create(ftpAddress + "/" + directoryName);
        request.Credentials = new NetworkCredential(username, password);
        request.Method = WebRequestMethods.Ftp.RemoveDirectory;

        FtpWebResponse response = (FtpWebResponse)request.GetResponse();
        Console.WriteLine("Directory deleted successfully.");
        response.Close();
    }

    public static void Main()
    {
        string ftpAddress = "ftp://ftp.example.com/";
        string username = "username";
        string password = "password";

        ListDirectory(ftpAddress, username, password);
        CreateDirectory(ftpAddress, username, password, "newDirectory");
        DeleteDirectory(ftpAddress, username, password, "newDirectory");
    }
}

在上面的示例中，ListDirectory方法用于列出FTP服務器上的目錄列表，CreateDirectory方法用于創建一個新目錄，DeleteDirectory方法用于刪除一個目錄。您可以根據需要自定義這些方法來執行不同的目錄操作。