private static MvcHtmlString GetMvcHtmlBySpOrCache(Func<MvcHtmlString> fun, string cacheKey, string spName)
        {
            if (CacheHelper.IsCached(cacheKey))
            {
                return CacheHelper.GetCacheValue(cacheKey) as MvcHtmlString;
            }

            SqlCacheDependency myDependency;
            string conString = WebConfigurationManager.ConnectionStrings["Db"].ConnectionString;
            using (SqlConnection connection = new SqlConnection(conString))
            {
                using (SqlCommand cmd = connection.CreateCommand())
                {
                    cmd.CommandText = spName;
                    cmd.CommandType = CommandType.StoredProcedure;
                    myDependency = new SqlCacheDependency(cmd);
                }
            }

            MvcHtmlString mvcHtmlString = fun();
            CacheHelper.AddCacheForever(cacheKey, mvcHtmlString, myDependency);
            return mvcHtmlString;
        }

以上代码不起作用，缓存后，更新数据后，缓存并不失效。：（

存储过程类似这样：

    --SET NOCOUNT ON;

    select top 24 a.x, COUNT(b.y) as count
    from dbo.XX a
        inner join dbo.YY b on b.mm = a.mm
    group by a.x
    order by a.Id desc;