Пример #1
0
        public void ProcessRequest(HttpContext Context)
        {
            #region Note
            //<img src="${siteurl}Timthumb.ashx?src=${item.Images.Bigimg}&amp;h=95&amp;w=142&amp;zc=1" width="142" height="95" alt="${item.title}" />
            #endregion

            Context.Response.Clear();
            Context.Response.ClearHeaders();
            Context.Response.ClearContent();
            Context.Response.ContentType = "image/jpeg";

            string static_cache  = "/cache/cache_images/";
            string static_random = "/common/images/random/tb";

            //宽度
            int w = VTSRequest.GetQueryInt("w");
            //高度
            int h = VTSRequest.GetQueryInt("h");

            //预留
            int zc = VTSRequest.GetQueryInt("zc");
            //图片地址
            string src = VTSRequest.GetQueryString("src");

            //原始 URL --一张图片一个唯一的URL地址
            string url = VTSRequest.GetRawUrl();

            //图片名字
            string md5 = MD5Encrypt.DataToMD5(url);

            //////////////开始分文件夹/////////////////
            string folderName = md5.Substring(0, 2);
            string imageDir   = Context.Server.MapPath(static_cache + folderName);

            if (!Directory.Exists(imageDir))
            {
                Directory.CreateDirectory(imageDir);
            }
            //////////////结束分文件夹/////////////////

            //物理地址
            string imageSavePath = string.Concat(imageDir, "\\", md5, ".jpg"); //Context.Server.MapPath("/cache/cache_images/" + md5 + ".jpg");

            //VTS.Log.LogOut.Info(string.Format("ManagedThreadId:{0} src:{1},url:{2}", System.Threading.Thread.CurrentThread.ManagedThreadId, src, url));
            /*******************************************************************************************************************************************************/
            byte[] b = null;

            if (File.Exists(imageSavePath))
            {
                #region 图片已存在

                #region 缓存策略
                //正确显示图片 才设置图片缓存策略
                //配置成一个星期 168小时
                Context.Response.Cache.SetExpires(DateTime.Now.AddHours(168));
                //下面的代码示例演示如何设置 Cache-Control: max-age 标题,为 0 小时,30 分钟和 0 秒。
                TimeSpan ts = new TimeSpan(168, 0, 0);
                Context.Response.Cache.SetMaxAge(ts);
                #endregion

                b = VTSCommon.GetPictureData(imageSavePath);
                Context.Response.OutputStream.Write(b, 0, b.Length);
                #endregion
            }
            else
            {
                #region 图片不存在

                #region 线程池生成
                ImagePackage image = new ImagePackage();
                image.Src      = src;
                image.SavePath = imageSavePath;
                image.Width    = w;
                image.Height   = h;

                //线程池生成
                WaitCallback callBack = new WaitCallback(GeneratePicture);
                ThreadPool.QueueUserWorkItem(callBack, image);

                //直接生成
                //GeneratePicture(image);
                #endregion

                #region 响应  随机
                imageSavePath = Context.Server.MapPath(string.Concat(static_random, ImageRandom.GetRandomInt().ToString(), ".jpg"));
                b             = VTSCommon.GetPictureData(imageSavePath);
                #endregion

                //清除缓存头策略
                Context.Response.Cache.SetCacheability(HttpCacheability.NoCache);
                Context.Response.Cache.SetNoStore();
                Context.Response.OutputStream.Write(b, 0, b.Length);
                #endregion
            }
            Context.ApplicationInstance.CompleteRequest();
        }