1 web.config配置如下；
<caching>
<!--enabled指示是否轮询更改。pollTime此值对应于连续两次轮询之间的毫秒数。不能设置为小于 500 毫秒的值。默认值为 1 分钟。-->
<sqlCacheDependency enabled="true" pollTime="60000">
<databases>
<add name="EduPortalCache" connectionStringName="EduPortalConn" />
</databases>
</sqlCacheDependency>
</caching>
<connectionStrings>
<add name="EduPortalConn" connectionString="User ID=sa;Initial Catalog=Portal;Data Source=localhost;Password=1111" providerName="System.Data.SqlClient" />
</connectionStrings>
2 打开 Visual Studio 2008 命令提示 执行如下命令：
aspnet_regsql -C "User ID=sa;Initial Catalog=Portal;Data Source=localhost;Password=1111" -ed -et -t "SSOPortal_PublishNewTrends"
aspnet_regsql -C "User ID=sa;Initial Catalog=Portal;Data Source=localhost;Password=1111" -ed -et -t "SSOPortal_PublishRecommendation"
查看那些表使用了缓存依赖
aspnet_regsql -C "User ID=sa;Initial Catalog=Portal;Data Source=localhost;Password=1111" –lt
3 代码如下：
/// <summary>
/// 获取当前应用程序指定CacheKey的Cache对象值
/// </summary>
/// <param name="CacheKey">索引键值</param>
/// <returns>返回缓存对象</returns>
public static object GetCache(string CacheKey)
{
System.Web.Caching.Cache objCache = HttpRuntime.Cache;
return objCache[CacheKey];
}
/// <summary>
/// 设置以缓存依赖的方式缓存数据
/// </summary>
/// <param name="CacheKey">索引键值</param>
/// <param name="objObject">缓存对象</param>
/// <param name="cacheDepen">依赖对象</param>
public static void SetCache(string CacheKey, object objObject, System.Web.Caching.CacheDependency dep)
{
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,
null);
}
/// <summary>
/// 绑定最新动态
/// </summary>
private void BindNews()
{
//EduPortal.BLL.SSOPortal_PublishNewTrends bll = new EduPortal.BLL.SSOPortal_PublishNewTrends();
//DataSet ds = bll.GetList(8, "", "OrdID DESC");
//repNews.DataSource = ds.Tables[0];
string CacheKey = "SSONEWS";
object objModel = CommonHelper.GetCache(CacheKey);//从缓存中获取
if (objModel == null)//缓存里没有
{
objModel = GetNews();//从数据库中获取
if (objModel != null)
{
//依赖数据库SSOPortal_PublishNewTrends表变化 来更新缓存
System.Web.Caching.SqlCacheDependency dep = new System.Web.Caching.SqlCacheDependency("EduPortalCache", "SSOPortal_PublishNewTrends");
CommonHelper.SetCache(CacheKey, objModel, dep);//写入缓存
}
}
repNews.DataSource = (DataTable)objModel;
repNews.DataBind();
}
/// <summary>
/// 获取最新动态
/// </summary>
/// <returns></returns>
private DataTable GetNews()
{
DataTable dt = null;
try
{
EduPortal.BLL.SSOPortal_PublishNewTrends bll = new EduPortal.BLL.SSOPortal_PublishNewTrends();
DataSet ds = bll.GetList(8, "", "OrdID DESC");
if (ds != null && ds.Tables[0].Rows.Count > 0)
{
dt = ds.Tables[0];
}
}
catch (Exception ex)
{
logger.Error(string.Format("操作类型：{0} 操作内容：{1} 操作用户：{2} 客户端IP：{3} 操作时间：{4} ", "最新动态", "最新动态-异常信息：" + ex.Message.ToString(), "", CommonHelper.GetIPAddress(), DateTime.Now.ToLocalTime()));
}
return dt;
}
4 参考文章