一，FileCache.aspx頁面
<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="FileCache.aspx.cs" Inherits="WebApplication1.FileCache" %> <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head runat="server"> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title></title> </head> <body> <form id="form1" runat="server"> <div> <asp:Label ID="Label1" runat="server" /> </div> </form> </body> </html>
二，FileCache.aspx.cs
using System; using System.Collections.Generic; using System.Linq; using System.Web; using System.Web.UI; using System.Web.UI.WebControls; using System.Xml.Linq; namespace WebApplication1 { public partial class FileCache : System.Web.UI.Page { /// <summary> /// 獲取當前應用程序指定CacheKey的Cache對象值 /// </summary> /// <param name="cacheKey">索引鍵值</param> /// <returns>返回緩存對象</returns> public static object GetCache(string cacheKey) { System.Web.Caching.Cache objCache = HttpRuntime.Cache; return objCache[cacheKey]; } /// <summary> /// 設置以緩存依賴的方式緩存數據 /// </summary> /// <param name="cacheKey">索引鍵值</param> /// <param name="objObject">緩存對象</param> /// <param name="dep"></param> public static void SetCache(string cacheKey, object objObject, System.Web.Caching.CacheDependency caDep) { System.Web.Caching.Cache objCache = HttpRuntime.Cache; objCache.Insert( cacheKey, objObject, caDep, System.Web.Caching.Cache.NoAbsoluteExpiration, //從不過期 System.Web.Caching.Cache.NoSlidingExpiration, //禁用可調過期 System.Web.Caching.CacheItemPriority.Default, null); } protected void Page_Load(object sender, EventArgs e) { Dictionary<string, string> dic = new Dictionary<string, string>(); string CacheKey = "CacheKey"; Dictionary<string, string> objModel = GetCache(CacheKey) as Dictionary<string, string>;//從緩存中獲取 if (objModel == null) //緩存里沒有 { string path = Server.MapPath("SX.xml"); //讀取服務器路徑下的XML文件，生成Dictionary儲存到緩存，並依賴這個文件 XElement root = XElement.Load(path); foreach (var item in root.Elements("Settings").Elements("row")) { var xAttribute = item.Attribute("Name"); if (xAttribute != null && !dic.ContainsKey(xAttribute.Value)) { dic.Add(xAttribute.Value, item.Attribute("Value").Value); } } System.Web.Caching.CacheDependency dep = new System.Web.Caching.CacheDependency(path); SetCache(CacheKey, dic, dep);//寫入緩存，並依賴SX.xml文件 } objModel = GetCache(CacheKey) as Dictionary<string, string>; if (objModel != null) Label1.Text = objModel["V"]; //當更改服務器的SX.xml的Name=V的value時，緩存會自動更新值 } } }
三，服務器下的SX.xml
<?xml version="1.0" encoding="utf-8"?> <root> <Settings> <row Name="V" Value="13"></row> <row Name="V1" Value="11"></row> <row Name="V2" Value="12"></row> </Settings> </root>
設計思路是：將XML文件讀取，儲存到Dictionary<string,string>中，並同時將這個Dictionary儲存到緩存並依賴XML文件，當XML文件發生變化是，緩存會自動更新改變的值