webform1.aspx
<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="WebForm1.aspx.cs" Inherits="work084.WebForm1" %> <!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>使用Cache的示例</title> </head> <body> <form id="form1" runat="server"> <div> <asp:TextBox ID="txtContent" runat="server" Columns="50" Rows="10" TextMode="MultiLine"></asp:TextBox> <asp:Button ID="Button1" runat="server" Text="显示文件内容" OnClick="Button1_Click" /> </div> </form> </body> </html>
webfrom1.aspx.cs
using System; using System.Collections.Generic; using System.Linq; using System.Web; using System.Web.UI; using System.Web.UI.WebControls; namespace work084 { public partial class WebForm1 : System.Web.UI.Page { protected void Page_Load(object sender, EventArgs e) { } protected void Button1_Click(object sender, EventArgs e) { string content = Cache["Content"] as string; if (content == null) { string path = Server.MapPath("~/Content.txt"); string text = System.IO.File.ReadAllText(path, System.Text.Encoding.UTF8); System.Web.Caching.CacheDependency dependency = new System.Web.Caching.CacheDependency(path); System.Web.Caching.CacheItemRemovedCallback callBack = new System.Web.Caching.CacheItemRemovedCallback(ItemRemovedCallBack); Cache.Add("Content", text, dependency, System.Web.Caching.Cache.NoAbsoluteExpiration, new TimeSpan(0,30,0), System.Web.Caching.CacheItemPriority.Default, callBack); txtContent.Text = text; } else { txtContent.Text = content; } } private void ItemRemovedCallBack(string key, object value, System.Web.Caching.CacheItemRemovedReason reason) { string path = Server.MapPath("~/Log.txt"); string log = string.Format("键为{0}的缓存项于{1}被删除,原因是:{2}。\r\n",key,DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss"),reason.ToString()); System.IO.File.AppendAllText(path, log); } } }