一，FileCache.aspx页面
<%@ 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>
/// 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="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, //从不过期
System.Web.Caching.Cache.NoSlidingExpiration, //禁用可调过期
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>;//从缓存中获取
if (objModel == null) //缓存里没有
{
string path = Server.MapPath("SX.xml"); //读取服务器路径下的XML文件，生成Dictionary储存到缓存，并依赖这个文件
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);//写入缓存，并依赖SX.xml文件
}
objModel = GetCache(CacheKey) as Dictionary<string, string>;
if (objModel != null) Label1.Text = objModel["V"]; //当更改服务器的SX.xml的Name=V的value时，缓存会自动更新值
}
}
}
三，服务器下的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>
设计思路是：将XML文件读取，储存到Dictionary<string,string>中，并同时将这个Dictionary储存到缓存并依赖XML文件，当XML文件发生变化是，缓存会自动更新改变的值
时间： 2024-10-02 07:39:04