Cookie的删除
最近在解决一个多语言的问题。 用到了cookie. 于是就想彻底了解一下cookie.没想到遇到了一个非常奇怪的问题，一直不得其解，就写这篇文章来这询问各位了。
环境：
vs2008和IE6
页面代码如下
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default"
UICulture="auto" Culture="auto" meta:resourcekey="PageResource1" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head> <title>Untitled Page</title></head><body> <form id="form1" runat="server"> <div> </div> <asp:Label ID="lblUserName" runat="server" meta:resourcekey="lblUserName" Text="Label"></asp:Label> <%--<asp:Label ID="lblUserName" runat="server" Text="<%$ Resources:Default.aspx.zh-CN.resx,lblUserName%>"></asp:Label>--%> <asp:Image ImageUrl="~/Images/213hws7.gif" ID="imgNew" runat="server" meta:resourcekey="imgNew" /> <asp:DropDownList ID="ddlMultiLanguage" runat="server" AutoPostBack="true" OnSelectedIndexChanged="ddlMultiLanguage_SelectedIndexChanged"> <asp:ListItem Value="en-us" Text="Englist" Selected="True"></asp:ListItem> <asp:ListItem Value="zh-cn" Text="简体中文"></asp:ListItem> </asp:DropDownList> <asp:Button ID="Button1" runat="server" onclick="Button1_Click" Text="Button" /> </form></body></html>
后台代码如下：
using System;using System.Configuration;using System.Data;using System.Linq;using System.Web;using System.Web.Security;using System.Web.UI;using System.Web.UI.HtmlControls;using System.Web.UI.WebControls;using System.Web.UI.WebControls.WebParts;using System.Xml.Linq;public partial class _Default : BasePage{
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack) { if (Request.Cookies["language_cookie"] != null && Request.Cookies["language_cookie"].Value != string.Empty) { string language_cookie = Request.Cookies["language_cookie"].Value.ToLower(); this.ddlMultiLanguage.SelectedValue = Request.Cookies["language_cookie"].Value.ToLower();
} else { this.ddlMultiLanguage.SelectedValue = Request.Headers["accept-language"].Split(",".ToCharArray())[0].ToString().ToLower(); } } } protected void ddlMultiLanguage_SelectedIndexChanged(object sender, EventArgs e) { if (Request.Cookies["language_cookie"] != null && Request.Cookies["language_cookie"].Value != string.Empty) { Request.Cookies["language_cookie"].Value = this.ddlMultiLanguage.SelectedValue; Request.Cookies["language_cookie"].Expires = DateTime.Now.AddDays(10); } else { Response.Cookies["language_cookie"].Value = this.ddlMultiLanguage.SelectedValue; Response.Cookies["language_cookie"].Expires = DateTime.Now.AddDays(10); } String selectedLanguage = this.ddlMultiLanguage.SelectedValue; UICulture = selectedLanguage; Culture = selectedLanguage; System.Threading.Thread.CurrentThread.CurrentCulture = System.Globalization.CultureInfo.CreateSpecificCulture(selectedLanguage); System.Threading.Thread.CurrentThread.CurrentUICulture = new System.Globalization.CultureInfo(selectedLanguage); } protected void Button1_Click(object sender, EventArgs e) { //Request.Cookies.Clear(); //Response.Cookies.Clear(); //Response.Cookies.Remove("language_cookie"); //Response.Cookies["language_cookie"].Expires = DateTime.Now.AddYears(-1000); Response.Cookies["language_cookie"].Expires = DateTime.Now.AddDays(-100); } protected override void InitializeCulture() { base.InitializeCulture(); }}
问题：
我在Button1_Click事件中，设置了cookie的过期时间，这样浏览器就可以删除cookie. 我查看了一下下面两个文件夹
C:\Documents and Settings\user\Cookies
C:\Documents and Settings\user\Local Settings\Temporary Internet Files
里边的cookie确实不存在了。
但是，当我再次启动程序，发现在 Page_Load事件中的Request.Cookies["language_cookie"]竟然还存在的。我个人觉得在点击button触发Button1_Click事件后，cookie应该是不删除了，再次启动程序的时候Request.Cookies["language_cookie"]应该是不存在的。所以很疑惑。请各位指教。
多谢多谢！
补充：当我设置一个很大的值Response.Cookies["language_cookie"].Expires = DateTime.Now.AddYears(-1000); 效果就与推断的一样。Request.Cookies["language_cookie"]就真的不存在了。
posted on 2009-06-29 11:37 3direction 阅读(1433) 评论(0) 编辑 收藏 举报
