Asp.Net数据库缓存依赖

        List<UserInfo> list = DataCache.GetCache("UserInfoCache") as List<UserInfo>;
        if (list == null)
        {
            System.Web.Caching.SqlCacheDependency dep = new System.Web.Caching.SqlCacheDependency("TestDB", "UserInfo");
            list = userManger.GetUserLoginList();
            onMoveBack = new CacheItemRemovedCallback(RemovedCallback);
            DataCache.SetCache("UserInfoCache", list, dep, onMoveBack);
        }

   CacheItemRemovedCallback onMoveBack;
    private void RemovedCallback(String k, Object v, CacheItemRemovedReason r)
    {
        onMoveBack = new CacheItemRemovedCallback(RemovedCallback);
        System.Web.Caching.SqlCacheDependency dep = new System.Web.Caching.SqlCacheDependency("TestDB", "UserInfo");
        List<UserInfo> list = userManger.GetUserLoginList();//从数据库中获取数据
      DataCache.SetCache("UserInfoCache", list, dep,onMoveBack);
    }

using System;
using System.Collections.Generic;
using System.Text;
using System.Web;
using System.Data;
using System.Data.SqlClient;
using System.Web.Caching;

public class DataCache
{
    /// <summary> 
    /// 获取当前应用程序指定CacheKey的Cache值 
    /// </summary> 
    /// <param name="CacheKey"></param> 
    /// <returns></returns> 
    public static object GetCache(string CacheKey)
    {
        System.Web.Caching.Cache objCache = HttpRuntime.Cache;
        return objCache[CacheKey];
    }
    /// <summary> 
    /// 设置当前应用程序指定CacheKey的Cache值 
    /// </summary> 
    /// <param name="CacheKey"></param> 
    /// <param name="objObject"></param> 
    public static void SetCache(string CacheKey, object objObject)
    {
        System.Web.Caching.Cache objCache = HttpRuntime.Cache;
        objCache.Insert(CacheKey, objObject);
    }
    /// <summary> 
    /// 设置已缓存依赖的方式缓存数据 
    /// </summary> 
    /// <param name="CacheKey">键值</param> 
    /// <param name="objObject">缓存对象</param> 
    /// <param name="dep">缓存依赖项</param> 
    /// <param name="onMoveCallBack">缓存项移除是触发的回调函数</param> 
    public static void SetCache(string CacheKey, object objObject, System.Web.Caching.CacheDependency dep, CacheItemRemovedCallback onMoveCallBack)
    {
        System.Web.Caching.Cache objCache = HttpRuntime.Cache;
        objCache.Insert(
        CacheKey,
        objObject,
        dep,
        System.Web.Caching.Cache.NoAbsoluteExpiration,//从不过期 
        System.Web.Caching.Cache.NoSlidingExpiration,//禁用可调过期 
        System.Web.Caching.CacheItemPriority.Default,
        onMoveCallBack
        );
    }
}