<configSections>

    <section name="fastdfs" type="FastDFS.Client.Config.FastDfsConfigurationSectionHandler, FastDFS.Client" />

  </configSections>

 <fastdfs>

    <FastDfsConfig GroupName="group1">

      <FastDfsServer IpAddress="192.168.88.103" Port="22122" />

    </FastDfsConfig>

  </fastdfs>

//文件保存到FastDFS服务器

var config = FastDfsManager.GetConfigSection();

ConnectionManager.InitializeForConfigSection(config);

StorageNode storageNode = FastDFSClient.GetStorageNode(config.GroupName);

string filePath = FastDFSClient.UploadFile(storageNode, file.Data, file.Extension.Replace(".", ""));        

private Task<byte[]> DownloadFileAsyn(string filePath)

        {

            return Task.Run(() =>

            {

                List<byte> content = new List<byte>();

                var config = FastDfsManager.GetConfigSection();

                ConnectionManager.InitializeForConfigSection(config);

                StorageNode storageNode = FastDFSClient.GetStorageNode(config.GroupName);

                FDFSFileInfo fileInfo = FastDFSClient.GetFileInfo(storageNode, filePath);

                if (fileInfo.FileSize >= )  //文件内容大于1024字节时，需要分批下载

                {

                    long offset = , len = ;

                    while (len > )

                    {

                        byte[] buffer = FastDFSClient.DownloadFile(storageNode, filePath, offset, len);

                        content.AddRange(buffer);

                        offset += len;

                        len = Math.Min(fileInfo.FileSize - offset, );

                    }

                }

                else

                {

                    content.AddRange(FastDFSClient.DownloadFile(storageNode, filePath));

                }

                return content.ToArray();

            });

        }

     　　　　// 从FastDFS服务器删除

            var config = FastDfsManager.GetConfigSection();

            ConnectionManager.InitializeForConfigSection(config);

            FastDFSClient.RemoveFile(config.GroupName, path);