/// <summary>/// 项目文件夹下路径  返回流类型数据，如：图片类型/// </summary>/// <returns></returns>public HttpResponseMessage GetImg(){  //  ~/ ImageFile / 001.png//项目文件夹下路径var imgPath = System.Web.Hosting.HostingEnvironment.MapPath("~/ImageFile/2.jpg");// 从图片中读取bytevar imgByte = File.ReadAllBytes(imgPath);// 从图片中读取流var imgStream = new MemoryStream(File.ReadAllBytes(imgPath));var resp = new HttpResponseMessage(HttpStatusCode.OK){Content = new StreamContent(imgStream)//或者//  Content = new ByteArrayContent(imgByte)
            };resp.Content.Headers.ContentType = new MediaTypeHeaderValue("image/jpg");return resp;}

 [HttpGet]public HttpResponseMessage SelectUploadFile(){Image img = Image.FromFile(@"C:\ImageFile\2.jpg");MemoryStream ms = new MemoryStream();img.Save(ms, System.Drawing.Imaging.ImageFormat.Png);HttpResponseMessage result = new HttpResponseMessage(HttpStatusCode.OK);result.Content = new ByteArrayContent(ms.ToArray());result.Content.Headers.ContentType = new MediaTypeHeaderValue("image/png"); //设置http响应上的Content-Type 为image/Png媒体类型return result;}

 [Route("Main")][HttpGet]public async Task<HttpResponseMessage> GetMain(string Ordernumber, int seq = 1){return await Task.FromResult<HttpResponseMessage>(GetFileImage("main", Ordertnumber, seq));}private HttpResponseMessage GetFileImage(string type, string Ordernumber, int seq){string basePath = @"C:\ImageFile\";string filePath = basePath + type + "\\_" + type + "_" + seq.ToString() + ".png";Image img = Image.FromFile(filePath);MemoryStream ms = new MemoryStream();img.Save(ms, System.Drawing.Imaging.ImageFormat.Png);HttpResponseMessage result = new HttpResponseMessage(HttpStatusCode.OK);result.Content = new ByteArrayContent(ms.ToArray());result.Content.Headers.ContentType = new MediaTypeHeaderValue("image/Png");return result;}