/// <summary>

        /// 大文件文件上传

        /// </summary>

        /// <param name="FilePath">上传文件保存路径</param>

        /// <param name="fileB">上传的二进制流</param>

        public void AcceptFile(string FilePath, Byte[] fileB)

        {

            FileStream fStream;

            //存在该文件追加，不存在创建

            if (File.Exists(FilePath))

            {

                fStream = new FileStream(FilePath, FileMode.Append, FileAccess.Write);

            }

            else

            {

                fStream = new FileStream(FilePath, FileMode.Create, FileAccess.Write);

            }

            fStream.Write(fileB, , fileB.Length);//把二进制流转文化文件

            fStream.Close();

        }

        /// <summary>

        /// 从指定文件夹大文件下载

        /// </summary>

        /// <param name="FileName">文件名</param>

        /// <param name="StartPosition">截取的开始位置</param>

        /// <param name="num">调用的次数</param>

        /// <param name="fileB">返回的二进制流</param>

        public void DownLoadFile(string FileName, int StartPosition, int num, string FilePath, out Byte[] fileB)

        {

            string[] ResourceDir = Directory.GetFiles(FilePath);

            Byte[] ResourceByte = {  };

            for (int i = ; i < ResourceDir.Length; i++)

            {

                FileStream fStream=new FileStream(ResourceDir[i].ToString(),FileMode.Open,FileAccess.Write);

                string ResourceName = ResourceDir[i].ToString().Substring(ResourceDir[i].LastIndexOf("\\") + );

                int iLen=*;//每次下载的大小，设置为1M

                //找到要下载的文件

                if (FileName == ResourceName)

                {

                    if (fStream.Length - num * iLen < iLen)

                    {

                        fStream.Seek(StartPosition, );

                        ResourceByte = new Byte[fStream.Length - num * iLen];

                        fStream.Read(ResourceByte, , (int)fStream.Length - num * iLen);

                    }

                    else

                    {

                        fStream.Seek(StartPosition, );//读取二进制流的指定位置

                        ResourceByte = new Byte[iLen];

                        fStream.Read(ResourceByte, , iLen);

                    }

                    fStream.Close();

                }

            }

            fileB = ResourceByte;

        }