ASP.NET cookie 操作详解cookie 写入、读取、修改、删除

ASP.NET cookie 操作详解cookie 写入、读取、修改、删除

一、操作详解：

    //写入    protected void Button2_Click(object sender, EventArgs e)     {         HttpCookie cookie=newHttpCookie("MyCook");//初使化并设置Cookie的名称         DateTime dt=DateTime.Now;         TimeSpan ts = new TimeSpan(0,0, 1,0,0);//过期时间为1分钟         cookie.Expires = dt.Add(ts);//设置过期时间         cookie.Values.Add("userid", "userid_value");         cookie.Values.Add("userid2","userid2_value2");         Response.AppendCookie(cookie);         //输出该Cookie的所有内容         //Response.Write(cookie.Value); //输出为：userid=userid_value&userid2=userid2_value2     }    //读取    protected void Button1_Click(object sender, EventArgs e)     {       // HttpCookie cokie =new HttpCookie("MyCook");//初使化        if(Request.Cookies["MyCook"]!=null)         {           //Response.Write("Cookie中键值为userid的值:" +Request.Cookies["MyCook"]["userid"]);//整行           //Response.Write("Cookie中键值为userid2的值" + Request.Cookies["MyCook"]["userid2"]);            Response.Write(Request.Cookies["MyCook"].Value);//输出全部的值         }     }    //修改Cookie    protected void Button3_Click(object sender, EventArgs e)     {        //获取客户端的Cookie对象         HttpCookie cok =Request.Cookies["MyCook"];               if (cok != null)         {         //修改Cookie的两种方法            cok.Values["userid"] = "alter-value";            cok.Values.Set("userid", "alter-value");          //往Cookie里加入新的内容             cok.Values.Set("newid", "newValue");             Response.AppendCookie(cok);         }          }    //删除Cookie    protected void Button4_Click(object sender, EventArgs e)     {         HttpCookiecok = Request.Cookies["MyCook"];        if (cok != null)         {            if(!CheckBox1.Checked)             {                cok.Values.Remove("userid");//移除键值为userid的值             }            else             {                TimeSpan ts = new TimeSpan(-1, 0, 0, 0);                cok.Expires = DateTime.Now.Add(ts);//删除整个Cookie，只要把过期时间设置为现在             }            Response.AppendCookie(cok);         }     }

二、分析：
   以前写程序都没去关注Cookie的应用，因为ASP.NET在客户端保存数据的方式比较多，且以前写的程序都没有用到Cookie，所以就没去了解，今天有个程序总是用Cookie出错。现在在网上查查Cookie的常用方法。
Cookie的用法也和ASP中差不多。比如我们建立一个名为user，值为111的cookie

方法一、

// 写入：HttpCookie cookie = new HttpCookie("user");cookie.Value = "111";Response.AppendCookie(cookie);// 我们取出Cookie值也很简单HttpCookie cookie = Request.Cookies["user"];cookieValue = cookie.Value;// 有时候我们想在一个Cookie中储存多个信息，那也没有问题。比如我们在名为user的cookie下加多个信息HttpCookie cookie = new HttpCookie("user");cookie.Values.Add("name","222");cookie.Values.Add("pwd","333");cookie.Values.Add("member","admin");Response.AppendCookie(cookie);// 从客户端获取取信息也一样简单HttpCookie cookie = Request.Cookies["user"];value1 = cookies.Values["name"];value2 = cookies.Values["pwd"];

方法二、

写入：HttpCookie cookie = new HttpCookie("id_admin_");cookie.Value = model.id_admin_.ToString();//cookie.Domain = ".sosuo8.com";HttpContext.Current.Response.Cookies.Add(cookie);cookie = new HttpCookie("name_admin_");//可能是中文字符，必须经过编码cookie.Value = HttpUtility.UrlEncode(model.name_admin_);//cookie.Domain = ".sosuo8.com";HttpContext.Current.Response.Cookies.Add(cookie);cookie = new HttpCookie("guid");cookie.Value = Guid.NewGuid().ToString();//cookie.Domain = ".sosuo8.com";HttpContext.Current.Response.Cookies.Add(cookie);读取：HttpContext.Current.Request.Cookies["guid"].Valueasp.net清空cookie 清空单个Response.Cookies["admin"].Expires = DateTime.Now.AddDays(-1);asp.net清空cookie 清空所有Request.Cookies.Clear()这个方法并不是删除Cookie 

删除 Cookie（即从用户的硬盘中物理移除 Cookie）是修改 Cookie 的一种形式。
由于 Cookie 在用户的计算机中，因此无法将其直接移除。
但是，可以让浏览器来为您删除 Cookie。
该技术是创建一个与要删除的 Cookie 同名的新Cookie，
并将该 Cookie 的到期日期设置为早于当前日期的某个日期。
当浏览器检查 Cookie 的到期日期时，浏览器便会丢弃这个现已过期的 Cookie。
下面的代码示例演示删除应用程序中所有可用 Cookie 的一种方法：

代码如下:

HttpCookie aCookie;string cookieName;int limit = Request.Cookies.Count;for (int i = 0; i < limit; i++){    cookieName = Request.Cookies[i].Name;    aCookie = new HttpCookie(cookieName);    aCookie.Expires = DateTime.Now.AddDays(-1);    Response.Cookies.Add(aCookie);}

Cookie封装类示例代码

using System;using System.Data;using System.Configuration;using System.Web;using System.Web.Security;using System.Web.UI;using System.Web.UI.WebControls;using System.Web.UI.WebControls.WebParts;using System.Web.UI.HtmlControls;public class Cookie{    /// <summary>    /// Cookies赋值    /// </summary>    /// <param name="strName">主键</param>    /// <param name="strValue">键值</param>    /// <param name="strDay">有效天数</param>    /// <returns></returns>    public bool setCookie(string strName, string strValue, int strDay)    {        try        {            HttpCookie Cookie = new HttpCookie(strName);            //Cookie.Domain = ".xxx.com";//当要跨域名访问的时候,给cookie指定域名即可,格式为.xxx.com            Cookie.Expires = DateTime.Now.AddDays(strDay);            Cookie.Value = strValue;            System.Web.HttpContext.Current.Response.Cookies.Add(Cookie);            return true;        }        catch        {            return false;        }    }    /// <summary>    /// 读取Cookies    /// </summary>    /// <param name="strName">主键</param>    /// <returns></returns>    public string getCookie(string strName)    {        HttpCookie Cookie = System.Web.HttpContext.Current.Request.Cookies[strName];        if (Cookie != null)        {            return Cookie.Value.ToString();        }        else        {            return null;        }    }    /// <summary>    /// 删除Cookies    /// </summary>    /// <param name="strName">主键</param>    /// <returns></returns>    public bool delCookie(string strName)    {        try        {            HttpCookie Cookie = new HttpCookie(strName);            //Cookie.Domain = ".xxx.com";//当要跨域名访问的时候,给cookie指定域名即可,格式为.xxx.com            Cookie.Expires = DateTime.Now.AddDays(-1);            System.Web.HttpContext.Current.Response.Cookies.Add(Cookie);            return true;        }        catch        {            return false;        }    }}

示例：

Cookie Cookie = new Cookie();Cookie.setCookie("name", "aaa",1);//赋值Cookie.getCookie("name");//取值Cookie.delCookie("name");//删除

注意:当Cookie存中文出现乱码,则在存放时给中文编码,如Cookie.setCookie("name",Server.UrlEncode("aaa"),1),读取时解码即可

另外：只要不给cookie设置过期时间,cookie在浏览器关闭的时候自动失效

 

转自：http://hi.baidu.com/3k_xiong/item/de2d73d330203eecb3f777a1