using System;using System.Collections.Generic;using System.Linq;using System.Web;using System.Web.Caching;namespace BusinessRules.Common{    /// <summary>    /// Cache高度缓存    /// </summary>    public class CacheManager    {        #region --Property--        private static string _cacheKey = String.Empty;        private static String _sqlDepName = "CacheData";        /// <summary>        /// 缓存索引键值        /// </summary>        public static string CacheKey        {            get { return CacheManager._cacheKey; }            set { CacheManager._cacheKey = value; }        }        /// <summary>        /// 缓存依赖名称        /// </summary>        public static String SqlDepName        {            get { return CacheManager._sqlDepName; }            set { CacheManager._sqlDepName = value; }        }        #endregion        #region --Method--        /// <summary>        /// 获取当前应用程序指定cacheKey的Cache对象值        /// </summary>        /// <param name="cacheKety">索引键值</param>        /// <returns>返回对象</returns>        public static Object GetCache(String cacheKey)        {            if (!String.IsNullOrEmpty(cacheKey))            {                Cache objCache = HttpRuntime.Cache;                return objCache[cacheKey];            }            else            {                return null;            }        }        /// <summary>        /// 获取当前应用程序指定cacheKey的Cache对象值        /// </summary>        /// <typeparam name="T">对象类型</typeparam>        /// <param name="cacheKey">索引键值</param>        /// <returns>返回对象类型</returns>        public static T GetCache<T>(String cacheKey)        {            object obj = GetCache(cacheKey);            return obj == null ? default(T) : (T)obj;        }        /// <summary>        /// 设置当前应用程序指定CacheKey的Cache对象值        /// </summary>        /// <param name="cacheKey">索引键值</param>        /// <param name="obj">c</param>        public static void SetCache(String cacheKey, Object obj)        {            Cache objCache = HttpRuntime.Cache;            objCache.Insert(cacheKey, obj);        }        /// <summary>        /// 创建缓存依赖项        /// </summary>        /// <param name="cacheKey"></param>        /// <param name="obj"></param>        /// <param name="fileName"></param>        public static void SetCache(String cacheKey, Object obj, String fileName)        {            CacheDependency cdep = new CacheDependency(fileName);            Cache objCache = HttpRuntime.Cache;            objCache.Insert(cacheKey, obj, cdep);        }        /// <summary>        /// 设置当前应用程序指定CacheKey的Cache对象值        /// </summary>        /// <param name="cacheKey">索引键值</param>        /// <param name="obj">索引键值</param>        /// <param name="absoluteExpiration">绝对过期时间</param>        /// <param name="slidingExpiration">最后一次访问所插入对象时与该对象过期时之间的时间间隔</param>        public static void SetCache(String cacheKey, Object obj, DateTime absoluteExpiration, TimeSpan slidingExpiration)        {            Cache objCache = HttpRuntime.Cache;            objCache.Insert(cacheKey, obj, null, absoluteExpiration, slidingExpiration);        }        /// <summary>        /// 创建缓存项过期        /// </summary>        /// <param name="cacheKey">索引键值</param>        /// <param name="obj">索引对象</param>        /// <param name="expires">过期时间</param>        public static void SetCache(String cacheKey, Object obj, Int32 expires)        {            Cache objCache = HttpRuntime.Cache;            objCache.Insert(            cacheKey,            obj,            null,            Cache.NoAbsoluteExpiration,//从不过期            new TimeSpan(0, expires, 0)            );        }        /// <summary>        /// 设置依赖的方式缓存数据        /// </summary>        /// <param name="cacheKey"></param>        /// <param name="obj"></param>        /// <param name="cdep"></param>        public static void SetCache(String cacheKey, Object obj, CacheDependency cdep)        {            Cache objCache = HttpRuntime.Cache;            objCache.Insert(                cacheKey,                obj,                cdep,                Cache.NoAbsoluteExpiration,//从不过期                Cache.NoSlidingExpiration,//禁用可调过期                CacheItemPriority.Default,                null                );        }        //==========调用方式Start===============        //    文件依赖使用说明        //    System.Web.Caching.CacheDependency dep = new System.Web.Caching.CacheDependency("C:\\test.txt");        //   SetCache(CacheKey, objModel, dep);//写入缓存        //        //  数据库依赖项使用说明        //   System.Web.Caching.SqlCacheDependency dep = new System.Web.Caching.SqlCacheDependency("codematic", "P_Product");        //  SetCache(CacheKey, objModel, dep);//写入缓存        //        //==========调用方式end===============        #endregion    }}

        //设置缓存的键值            CacheManager.CacheKey = "NavMenue";            //获取当前键值下的缓存数据            Object cacheModel = CacheManager.GetCache(CacheManager.CacheKey);            //如果缓存中不存在当前键值对象            if (cacheModel == null)            {                //将数据存储到缓存中                cacheModel = bsnManage.Obj_List(navPosition);                if (cacheModel != null)                {                    //依赖数据库的sc_navigation 表变化来更新                    SqlCacheDependency scdep = new SqlCacheDependency(CacheManager.SqlDepName, "sc_navigation");                    //写入缓存                    CacheManager.SetCache(CacheManager.CacheKey, cacheModel, scdep);                }                return (DataTable)cacheModel;            }            else                return (DataTable)CacheManager.GetCache(CacheManager.CacheKey);