c# api接口 文件处理

    /// <summary>
        /// POST api/FileManager/PostFormData
        /// </summary>
        /// <returns></returns>
        [ActionName("PostFormData")]
        [HttpPost]
        public async Task<HttpResponseMessage> PostFormData()
        {
            // Check if the request contains multipart/form-data.
            // 检查该请求是否含有multipart/form-data
            if (!Request.Content.IsMimeMultipartContent())
            {
                throw new HttpResponseException(HttpStatusCode.UnsupportedMediaType);
            }
            string root = HttpContext.Current.Server.MapPath(PortraitApp);
            var provider = new MultipartFormDataStreamProvider(root);

            try
            {
                // Read the form data.
                // 读取表单数据
                await Request.Content.ReadAsMultipartAsync(provider);

                // This illustrates how to get the file names.
                // 以下描述如何获取文件名
                foreach (MultipartFileData file in provider.FileData)
                {
                    Trace.WriteLine(file.Headers.ContentDisposition.FileName);
                    Trace.WriteLine("Server file path: " + file.LocalFileName);
                }
                return Request.CreateResponse(HttpStatusCode.OK);
            }
            catch (System.Exception e)
            {
                return Request.CreateErrorResponse(HttpStatusCode.InternalServerError, e);
            }
        }

        /// <summary>
        /// POST api/FileManager/PostFormFile
        /// </summary>
        /// <returns></returns>
        [ActionName("PostFormFile")]
        [HttpPost]
        public IHttpActionResult PostFormFile()
        {
            try
            {
                if (!Directory.Exists(HttpContext.Current.Server.MapPath(PortraitApp)))
                {
                    Directory.CreateDirectory(HttpContext.Current.Server.MapPath(PortraitApp));
                }

                HttpFileCollection files = HttpContext.Current.Request.Files;
                string name = "";
                foreach (string key in files.AllKeys)
                {
                    HttpPostedFile file = files[key];

                    if (string.IsNullOrEmpty(file.FileName) == false)
                    {
                        int length = file.ContentLength;
                        if (length>2097152)
                        {
                            throw new CustomException("上传文件超过2M,请将上传文件大小控制在2M内,谢谢");
                        }
                        string extension = file.FileName.Substring(file.FileName.LastIndexOf(‘.‘)).ToLower();
                        if (extension!=".bmp"&& extension != ".jpg" && extension != ".jpeg" && extension != ".png")
                        {
                            throw new CustomException("上传文件扩展名不正确,请上传bmp,jpg,jpeg,png格式的图片");
                        }

                        name = DateTime.Now.ToStringByDatetime(DateTimeType.yyyyMMddHHmmss) + extension;
                        //LoginVerifyModels usermodel = GetVerifyModel();
                        string username = GetVerifyString();
                        if (!string.IsNullOrEmpty(username))
                        {
                            name = username + extension; 
                        }
                        file.SaveAs(HttpContext.Current.Server.MapPath(PortraitApp) + name);

                    }
                }

                return Json(Success(new { ImgPath = RetureTemp + name }));
            }
            catch (CustomException ce)
            {
                return Json(getException(ce.Message));
            }
            catch (Exception ex)
            {
                return Json(getException(ex));
            }
        }