问如何使用Tamir.SharpSsh.Sftp区分文件和目录

EN

 public List<DirectoryItem> ConnectSFTP(string address, string username, string password, Tamir.SharpSsh.Sftp ObjClient,string strfolder)
        {
            List<DirectoryItem> returnValue = new List<DirectoryItem>();
            bool status = false;
            try
            {

                System.Collections.ArrayList list = new System.Collections.ArrayList();
                //Tamir.SharpSsh.Sftp client = new Tamir.SharpSsh.Sftp(address + @"/ToNationwide/ivl00018/", username, password);
                Tamir.SharpSsh.Sftp client = (ObjClient == null) ? new Tamir.SharpSsh.Sftp(address, username, password) : ObjClient;
                client.Connect();
                System.Collections.ArrayList arr = client.GetFileList(strfolder);

                foreach (var item in arr)
                {
                    if (item.ToString() != "." && item.ToString() != "..")
                    {
                        list.Add(item);
                    }

                }

                foreach (string line in list)
                {
                    // Windows FTP Server Response Format
                    // DateCreated    IsDirectory    Name

                    // Parse <DIR>
                    bool isDirectory = client.GetFileList(strfolder+"/"+line).Count > 1;// Here i am confuse how to identify is directory or not ?

                    string name = line.ToString();
                    // Create directory info
                    DirectoryItem item = new DirectoryItem();
                    item.BaseUri = address;
                    item.IsDirectory = isDirectory;
                    item.Name = name;


                    item.Items = item.IsDirectory ? ConnectSFTP(item.AbsolutePath, username, password, client, "/"+line) : null;

                    returnValue.Add(item);
                }

                client.Close();
                status = true;
            }

            catch (Exception ex)
            {
            }
            return returnValue;
        }
    }