public class FileDownLoadController : BaseController
    {

        private  string FileFolder = ConfigurationManager.AppSettings["DownFile"];//获取值

         


        #region 下载

        #region 下载文件服务器方法


        /// <summary>
        /// 下载文件服务器方法
        /// </summary>
        /// <param name="fileName"></param>
        /// <returns></returns> 
        public HttpResponseMessage GetDownLoad(string fileName)
        {

            HttpResponseMessage result = null;

            try
            {

                DirectoryInfo directoryInfo = new DirectoryInfo(FileFolder);
 
                FileInfo foundFileInfo = directoryInfo.GetFiles().Where(x => x.Name == fileName).FirstOrDefault();
 
                if (foundFileInfo != null)
                {
                    FileStream fs = new FileStream(foundFileInfo.FullName, FileMode.Open);

                    result = new HttpResponseMessage(HttpStatusCode.OK);
                    result.Content = new StreamContent(fs);
                    result.Content.Headers.ContentType = new System.Net.Http.Headers.MediaTypeHeaderValue("application/octet-stream");
                    result.Content.Headers.ContentDisposition = new ContentDispositionHeaderValue("attachment");
                    result.Content.Headers.ContentDisposition.FileName = foundFileInfo.Name;
                }
                else
                {
                    result = new HttpResponseMessage(HttpStatusCode.NotFound);
                }


            }
            catch (Exception ex)
            {
                log.Error(ex.StackTrace);
                throw ex;
            }

            return result;
        }

        #endregion





        #endregion
    }