/// <summary>

        /// 上传文件

        /// </summary>

        /// <param name="fileinfo">需要上传的文件</param>

        /// <param name="targetDir">目标路径</param>

        /// <param name="hostname">ftp地址</param>

        /// <param name="username">ftp用户名</param>

        /// <param name="password">ftp密码</param>

        public static void UploadFile(FileInfo fileinfo, string targetDir, string hostname, string username, string password)

        {

            string target;

            if (targetDir.Trim() == "")

            {

                return;

            }

            target = Guid.NewGuid().ToString();  //使用临时文件名

            string URI = "FTP://" + hostname + "/" + targetDir + "/" + target;

            ///WebClient webcl = new WebClient();

            System.Net.FtpWebRequest ftp = GetRequest(URI, username, password);

            //指定文件传输的数据类型

            ftp.UseBinary = true;

            ftp.UsePassive = true;

            //设置FTP命令 设置所要执行的FTP命令，

            //ftp.Method = System.Net.WebRequestMethods.Ftp.ListDirectoryDetails;//假设此处为显示指定路径下的文件列表

            ftp.Method = System.Net.WebRequestMethods.Ftp.UploadFile;

            //告诉ftp文件大小

            ftp.ContentLength = fileinfo.Length;

            //缓冲大小设置为2KB

            const int BufferSize = ;

            byte[] content = new byte[BufferSize -  + ];

            int dataRead;

            //打开一个文件流 (System.IO.FileStream) 去读上传的文件

            using (FileStream fs = fileinfo.OpenRead())

            {

                try

                {

                    //把上传的文件写入流

                    using (Stream rs = ftp.GetRequestStream())

                    {

                        do

                        {

                            //每次读文件流的2KB

                            dataRead = fs.Read(content, , BufferSize);

                            rs.Write(content, , dataRead);

                        } while (!(dataRead < BufferSize));

                        rs.Close();

                    }

                }

                catch (Exception ex)

                {

                    throw new Exception(ex.Message);

                }

                finally

                {

                    fs.Close();

                }

            }

            ftp = null;

            //设置FTP命令

            ftp = GetRequest(URI, username, password);

            ftp.Method = System.Net.WebRequestMethods.Ftp.Rename; //改名

            ftp.RenameTo = fileinfo.Name;

            try

            {

                ftp.GetResponse();

            }

            catch (Exception ex)

            {

                ftp = GetRequest(URI, username, password);

                ftp.Method = System.Net.WebRequestMethods.Ftp.DeleteFile; //删除

                ftp.GetResponse();

                throw ex;

            }

            finally

            {

               fileinfo.Delete();

            }

            // 可以记录一个日志  "上传" + fileinfo.FullName + "上传到" + "FTP://" + hostname + "/" + targetDir + "/" + fileinfo.Name + "成功." );

            ftp = null;

        }

        private static FtpWebRequest GetRequest(string URI, string username, string password)

        {

            //根据服务器信息FtpWebRequest创建类的对象

            FtpWebRequest result = (FtpWebRequest)FtpWebRequest.Create(URI);

            //提供身份验证信息

            result.Credentials = new System.Net.NetworkCredential(username, password);

            //设置请求完成之后是否保持到FTP服务器的控制连接，默认值为true

            result.KeepAlive = false;

            return result;

        }

        #endregion