/// <summary>    /// CacheHttpModule类    /// </summary>    internal class CacheHttpModule : IHttpModule    {        public void Dispose()        {        }        private List<string> listNeedCacheExtend;        private string stringClearCache = "zzl";//域名中第一段 url 如果是此字符，则表示此次请求是清除缓存 如： http://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)) //检测当前请求是否需缓存            {                string key = string.Empty; ;                string extend = VirtualPathUtility.GetExtension(application.Context.Request.FilePath).ToLower();                if (IsClearCache(application, out key))                {                    if (CacheManage.Container(key, extend))//缓存中存在，则清除缓存，结束请求                    {                        application.Context.Response.Write(CacheManage.Remove(key, extend));                    }                    application.CompleteRequest();                }                else                {                    #region 使用页面压缩                    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))//缓存中存在，则直接返回内容，结束请求                    {                        CacheManage.Write(application, key);                        application.CompleteRequest();                    }                }            }        }        /// <summary>        /// 检测当前请求是否需缓存,如果是则将此次结果添加至缓存,如果此次请求出错，不会执行至此        /// </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;                    //是否需要添加缓存，                    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>        /// 检测当前请求类型(url扩展名)确定是否需缓存        /// 如果类型需缓存，但扩展名是html或htm且存在相对应的物理文件的，不执行缓存操作        /// </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扩展名是否满足条件            {                boolNeedCache = listNeedCacheExtend.Contains(stringExtend);            }            if (boolNeedCache)            {                if (stringExtend == ".html" || stringExtend == ".htm")                {                    if (System.IO.File.Exists(application.Context.Request.PhysicalPath)) //存在对应物理文件                    {                        boolNeedCache = false;                    }                }            }            return boolNeedCache;        }        /// <summary>        /// 检测当次请求是否是清除缓存的         /// True 清除缓存  False  不是清除缓存的        /// </summary>        /// <param name="application"></param>        /// <param name="url">真实的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("http://" + domain + "/" + stringClearCache + "/", RegexOptions.Singleline | RegexOptions.Compiled | RegexOptions.IgnoreCase);            if (regex.IsMatch(url))            {                boolClearCache = true;                url = "http://" + domain + "/" + url.Replace(regex.Match(url).Captures[0].Value, string.Empty);            }            return boolClearCache;        }        /// <summary>        /// 获取客户端支持的压缩类型        /// </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>