1 使用cache.Insert方法时，新建一个System.Web.Caching.CacheDependency对象，告诉缓存，当缓存的内容发生变化时，将删除缓存，并重新缓存
using System;using System.Collections.Generic;using System.Linq;using System.Web;using System.Web.UI;using System.Web.UI.WebControls;using System.IO;namespace Cachting{ ???public class CityListInfo ???{ ???????public string Timestamp { get; set; } ???????public string Html { get; set; } ???} ???public partial class CitiesControl : System.Web.UI.UserControl ???{ ???????private static readonly string fileName = "/CitiesList.html"; ???????private static readonly string CACHE_KEY = "cities_html"; ???????private CityListInfo cityInfo; ???????private bool cached = false; ???????protected void Page_Load(object sender, EventArgs e) ???????{ ???????????cityInfo = Cache[CACHE_KEY] as CityListInfo; ???????????if (cityInfo==null) ???????????{ ???????????????cityInfo = new CityListInfo { Timestamp=DateTime.Now.ToLongTimeString(), ???????????????????Html =File.ReadAllText(MapPath(fileName))}; ???????????????//只要未修改文件就应该缓存数据 ???????????????Cache.Insert(CACHE_KEY, cityInfo,new System.Web.Caching.CacheDependency(MapPath(fileName))); ???????????} ???????????else ???????????{ ???????????????cached = true; ???????????} ???????} ???????public string GetCities() ???????{ ???????????//return File.ReadAllText(MapPath(fileName)); ???????????return cityInfo.Html; ???????} ???????public string GetTimeStamp() ???????{ ???????????// return DateTime.Now.ToLongTimeString(); ???????????return cityInfo.Timestamp + (cached ? "<b>Cached</b>" : ""); ???????} ???}}asp.net 自动检测缓存内容是否变化
原文地址：http://www.cnblogs.com/mibing/p/7791777.html