public class FtpFile
    {
        string ftpServerIP;

        public string FtpServerIP
        {
            get { return ftpServerIP; }
            set { ftpServerIP = value; }
        }
        string ftpUserID;

        public string FtpUserID
        {
            get { return ftpUserID; }
            set { ftpUserID = value; }
        }
        string ftpPassword;

        public string FtpPassword
        {
            get { return ftpPassword; }
            set { ftpPassword = value; }
        }
        FtpWebRequest reqFTP;
        public static string FtpServer = System.Configuration.ConfigurationSettings.AppSettings["FtpServer"];
        public static string FtpUser = System.Configuration.ConfigurationSettings.AppSettings["FtpUser"];
        public static string FtpPwd = System.Configuration.ConfigurationSettings.AppSettings["FtpPwd"];
        private void Connect(String path)//连接ftp
        {
            // 根据uri创建FtpWebRequest对象
            reqFTP = (FtpWebRequest)FtpWebRequest.Create(new Uri(path));
            // 指定数据传输类型
            reqFTP.UseBinary = true;
            // ftp用户名和密码
            reqFTP.Credentials = new NetworkCredential(ftpUserID, ftpPassword);
        }
        public FtpFile(string ftpServerIP, string ftpUserID, string ftpPassword)
        {
            this.ftpServerIP = ftpServerIP;
            this.ftpUserID = ftpUserID;
            this.ftpPassword = ftpPassword;
        }
        public FtpFile()
        {
            this.ftpServerIP = FtpServer;
            this.ftpUserID = FtpUser;
            this.ftpPassword = FtpPwd;
        }
    }

------解决方案--------------------

你可以启个线程在那里，线程启动后连上FTP,然后循环检查上传或下载的任务，如果有任务就一个一个的处理，在程序退出时再关闭连接。