/// <summary>
    /// CacheHttpModule類(lei)
    /// </summary>
    internal class CacheHttpModule : IHttpModule
    {
        public void Dispose()
        {
        }
        private List<string> listNeedCacheExtend;
        private string stringClearCache = "zzl";//域名中第(di)一段 url 如(ru)果(guo)是此字符，則表示此次(ci)請求是清除緩(huan)存 如(ru)： //www.domain.com/zzl/*******
        public void Init(HttpApplication context)
        {
            context.BeginRequest += new EventHandler(context_BeginRequest);
            context.ReleaseRequestState += new EventHandler(context_ReleaseRequestState);

            listNeedCacheExtend = new List<string>();
            string extends = WebConfig.GetUserSection("CacheInfo", "ExtendTypes", ".html|.htm");
            foreach (string s in extends.Split('|'))
            {
                if (!string.IsNullOrEmpty(s) && !listNeedCacheExtend.Contains(s.Trim()))
                    listNeedCacheExtend.Add(s.Trim());
            }

        }

        public void context_BeginRequest(object sender, EventArgs e)
        {
            var application = (HttpApplication)sender;

            if (IsNeedCache(application)) //檢測當前請求(qiu)是否需(xu)緩存
            {
                string key = string.Empty; ;
                string extend = VirtualPathUtility.GetExtension(application.Context.Request.FilePath).ToLower();
                if (IsClearCache(application, out key))
                {
                    if (CacheManage.Container(key, extend))//緩存中存在，則清除緩存，結束(shu)請求
                    {
                        application.Context.Response.Write(CacheManage.Remove(key, extend));
                    }
                    application.CompleteRequest();
                }
                else
                {
                    #region 使用頁面壓縮

                    ResponseCompressionType compressionType = this.GetCompressionMode(application.Context.Request);
                    if (compressionType != ResponseCompressionType.None)
                    {
                        application.Context.Response.AppendHeader("Content-Encoding", compressionType.ToString().ToLower());
                        if (compressionType == ResponseCompressionType.GZip)
                        {
                            application.Context.Response.Filter = new GZipStream(application.Context.Response.Filter, CompressionMode.Compress);
                        }
                        else
                        {
                            application.Context.Response.Filter = new DeflateStream(application.Context.Response.Filter, CompressionMode.Compress);
                        }
                    }

                    #endregion
                    if (CacheManage.Container(key, extend))//緩(huan)存中(zhong)存在，則直接(jie)返(fan)回內容，結束請求
                    {
                        CacheManage.Write(application, key);
                        application.CompleteRequest();
                    }
                }



            }
        }

        /// <summary>
        /// 檢測(ce)當前請求是否需緩(huan)存,如果是則將此(ci)次結果添加(jia)至(zhi)緩(huan)存,如果此(ci)次請求出錯，不(bu)會執行(xing)至(zhi)此(ci)
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        public void context_ReleaseRequestState(object sender, EventArgs e)
        {
            var application = (HttpApplication)sender;
            if (application.Context.Response.StatusCode == 200)
            {
                string strT = null;
                string extend = VirtualPathUtility.GetExtension(application.Context.Request.FilePath).ToLower();
                if (IsNeedCache(application) && !IsClearCache(application, out strT))
                {
                    string key = application.Context.Request.Url.AbsoluteUri;
                    //是(shi)否需要(yao)添加緩存(cun)，
                    if (!CacheManage.Container(key, extend))
                    {
                        application.Context.Response.Filter = new ResponseFilter(application.Context.Response.Filter, key, extend, application.Context.Response.ContentEncoding);
                    }
                }
            }
        }

        public void context_EndRequest(object sender, EventArgs e)
        {
            var application = (HttpApplication)sender;
            string key = application.Context.Request.Url.AbsoluteUri;
            application.Context.Response.Write("<Br>CacheMdule EndRequest");
        }

        /// <summary>
        /// 檢測當前請求類型(url擴展(zhan)名(ming))確定(ding)是否(fou)需緩存
        /// 如果類型(xing)需緩存(cun)，但擴展名是html或htm且存(cun)在相對(dui)應的物理文(wen)件的，不執行緩存(cun)操(cao)作
        /// </summary>
        /// <param name="strFilePath"></param>
        /// <returns></returns>
        private bool IsNeedCache(HttpApplication application)
        {
            bool boolNeedCache = false;
            string stringExtend = VirtualPathUtility.GetExtension(application.Context.Request.FilePath).ToLower();
            if (null != listNeedCacheExtend) //url擴展名是否滿足條件
            {
                boolNeedCache = listNeedCacheExtend.Contains(stringExtend);
            }

            if (boolNeedCache)
            {
                if (stringExtend == ".html" || stringExtend == ".htm")
                {
                    if (System.IO.File.Exists(application.Context.Request.PhysicalPath)) //存在對應物理文件
                    {
                        boolNeedCache = false;
                    }
                }
            }
            return boolNeedCache;
        }

        /// <summary>
        /// 檢測當次請求是否是清除緩(huan)存的(de) 
        /// True 清(qing)除(chu)緩存(cun)  False  不是清(qing)除(chu)緩存(cun)的(de)
        /// </summary>
        /// <param name="application"></param>
        /// <param name="url">真實(shi)的URL地址</param>
        /// <returns></returns>
        private bool IsClearCache(HttpApplication application, out string url)
        {
            bool boolClearCache = false;
            url = application.Context.Request.Url.AbsoluteUri;
            string domain = application.Context.Request.Url.Host;
            Regex regex = new Regex("//" + domain + "/" + stringClearCache + "/", RegexOptions.Singleline | RegexOptions.Compiled | RegexOptions.IgnoreCase);
            if (regex.IsMatch(url))
            {
                boolClearCache = true;
                url = "//" + domain + "/" + url.Replace(regex.Match(url).Captures[0].Value, string.Empty);
            }
            return boolClearCache;
        }


        /// <summary>
        /// 獲取(qu)客(ke)戶端支持(chi)的壓縮類型
        /// </summary>
        /// <param name="request"></param>
        /// <returns></returns>
        private ResponseCompressionType GetCompressionMode(System.Web.HttpRequest request)
        {
            string acceptEncoding = request.Headers["Accept-Encoding"];
            if (string.IsNullOrEmpty(acceptEncoding))
                return ResponseCompressionType.None;

            acceptEncoding = acceptEncoding.ToUpperInvariant();
            if (acceptEncoding.Contains("GZIP"))
                return ResponseCompressionType.GZip;
            else if (acceptEncoding.Contains("DEFLATE"))
                return ResponseCompressionType.Deflate;
            else
                return ResponseCompressionType.None;
        }

        private enum ResponseCompressionType
        {
            None, GZip, Deflate
        }

    }

　 <modules runAllManagedModulesForAllRequests="true" >
      <add name="CacheHttpModule" type="HttpModuleCache.CacheHttpModule,HttpModuleCache"/>
    </modules>