//这是标题图片上传方法
                if (image != null)
                {
                    string year = DateTime.Now.Year.ToString();
                    string month = DateTime.Now.Month.ToString("00");
                    string day = DateTime.Now.Day.ToString("00");

                    string fileFolder = string.Concat("Upload/", year, "/", month, "/", day);
                    string path = HostingEnvironment.MapPath("~/" + fileFolder);

                    if (!Directory.Exists(path))
                    {
                        //在Upload目录下创建了一个文件夹   
                        Directory.CreateDirectory(path);
                    }
                    string imagename = image.FileName;
                    string fileType = Path.GetExtension(image.FileName).ToLower();
                    if (fileType == ".jpeg" || fileType == ".jpg" || fileType == ".png" || fileType == ".gif")
                    {
                        Random ran = new Random();
                        string ename = DateTime.Now.ToString("yyyyMMddhhmmssfff") + ran.Next(9999);
                        //上传后生成的图片名
                        string name = ename + fileType;

                        image.SaveAs(Path.Combine(path, name));
                        string imageurl = string.Concat(HostingEnvironment.ApplicationVirtualPath, fileFolder, "/", name);

                        //生成标题图片
                        //缩略图名
                        string thumbName = ename + "_500x200" + fileType;

                        //缩略图绝对路径
                        string thumbPath = string.Concat(HostingEnvironment.ApplicationPhysicalPath, fileFolder, "/", thumbName);

                        // 设置缩略图保存路径
                        FileStream stream = new FileStream(Path.GetFullPath(thumbPath), FileMode.OpenOrCreate);

                        // 缩放上传的文件
                        Image OrigImage = Image.FromStream(image.InputStream);



                        // 创建缩略图对象
                        Bitmap TempBitmap = new Bitmap(550, 200);
                        // 创建缩略图画质
                        Graphics NewImage = Graphics.FromImage(TempBitmap);
                        NewImage.CompositingQuality = CompositingQuality.HighQuality;
                        NewImage.SmoothingMode = SmoothingMode.HighQuality;
                        NewImage.InterpolationMode = InterpolationMode.HighQualityBicubic;
                        // 创建Rectangle对象进行绘制
                        Rectangle imageRectangle = new Rectangle(0, 0, 550, 200);
                        NewImage.DrawImage(OrigImage, imageRectangle);
                        // 保存缩略图
                        TempBitmap.Save(stream, OrigImage.RawFormat);
                        // 释放资源
                        NewImage.Dispose();
                        TempBitmap.Dispose();
                        OrigImage.Dispose();
                        stream.Close();
                        stream.Dispose();

                        newArticle.ImageUrl = imageurl;
                    }
                }

/// <summary>
/// 获取一个图片按等比例缩小后的大小。
/// </summary>
/// <param name="maxWidth">需要缩小到的宽度</param>
/// <param name="maxHeight">需要缩小到的高度</param>
/// <param name="imageOriginalWidt