【转】写入和读取cookie数组

Cookie是一段文本信息,在客户端存储 Cookie 是 ASP.NET 的会话状态将请求与会话关联的方法之一。Cookie 也可以直接用于在请求之间保持数据，但数据随后将存储在客户端并随每个请求一起发送到服务器。浏览器对 Cookie 的大小有限制，因此，只有不超过 4096 字节才能保证被接受。

编写Cookie



//方式1:
Response.Cookies["username"].value="mike";
Response.Cookies["username"].Expires=DateTime.MaxValue;

//方式2:
HttpCookie acookie = new HttpCookie("last");
acookie.Value="a";
acookie..Expires=DateTime.MaxValue;
Response.Cookies.Add(acookie);

//多值Cookie的写法

//方式1:
Response.Cookies["userinfo1"]["name"].value="mike";
Response.Cookies["userinfo1"]["last"].value="a";
Response.Cookies["userinfo1"].Expires=DateTime.MaxValue;

//方式2:
HttpCookie cookie = new HttpCookie("userinfo1");
cookie.Values["name"]="mike";
cookie.Values["last"]="a";
cookie.Expires=DateTime.MaxValue;
//cookie.Expires = System.DateTime.Now.AddDays(1);//设置过期时间  1天
Response.Cookies.Add(cookie);




读取Cookie
Internet Explorer 将站点的 Cookie 保存在文件名格式为 <user>@<domain>.txt 的文件中，其中 <user> 是您的帐户名。
注意:在获取Cookie的值之前，应该确保该 Cookie 确实存在。否则，您将得到一个异常




If (Request.Cookies["userName"]!=null)
{
  string str = Request.Cookies("userName").Value;
}

//多值Cookie的读取
If ( Request.Cookies["userInfo1"]!=null )
{
  string name=Request.Cookies["userInfo1"]["name"];
  string last=Request.Cookies["userInfo1"]["last"];
}


//读取 Cookie 集合
for(int i = 0 ;i<Request.Cookies.Count ;i++)
{
    HttpCookie cookies = Request.Cookies;
    Response.Write("name="+cookies.Mame+"<br/>");
    if (cookies.HasKeys )//是否有子键
    {
        System.Collections.Specialized.NameValueCollection NameColl
                                             = aCookie.Values ;
        for(int j=0;j<NameColl.Count;j++)
        {
            Response.Write("子键名="+ NameColl.AllKey[j] +"<br/>");
            Response.Write("子键值="+ NameColl[j] +"<br/>");
        }

    }
    else
    {
        Response.Write("value="+cookies.Value+"<br/>");       
    }
}




运行此代码时，可看到一个名为“ASP.NET_SessionId”的Cookie，ASP.NET用这个 Cookie 来保存您的会话的唯一标识符。

修改 Cookie
修改的方法与创建方法相同


删除 Cookie
将其有效期设置为过去的某个日期。当浏览器检查 Cookie 的有效期时，就会删除这个已过期的 Cookie。



HttpCookie cookie = new HttpCookie("userinfo1");
cookie.Expires=DateTime.Now.AddDays(-30);
Response.Cookies.Add(cookie);

============================实例。


//----------写入Cookie
HttpCookie cookie = new HttpCookie("userinfo1");
        cookie.Expires = System.DateTime.Now.AddMinutes(2);//设置过期时间
        for (int i = 0; i < 20; i++)
        {
           
            cookie.Values["Val" +i.ToString()] = i.ToString();          
            Response.Cookies.Add(cookie);
        }

//读取 Cookie 集合
        for (int i = 0; i < Request.Cookies.Count; i++)
        {
            if (Request.Cookies.AllKeys[i] == "userinfo1")
            {

                HttpCookie cookies = Request.Cookies["userInfo1"];
                Response.Write("name=" + cookies.Name + "<br/>");
                //Response.Write("name=" + cookies.Value + "<br/>");

                if (cookies.HasKeys)//是否有子键
                {
                    System.Collections.Specialized.NameValueCollection NameColl = cookies.Values;
                    for (int j = 0; j < NameColl.Count; j++)
                    {
                        Response.Write("子键名=" + NameColl.AllKeys[j] + "<br/>");
                        Response.Write("子键值=" + NameColl[j] + "<br/>");
                    }

                }
                else
                {
                    Response.Write("value=" + cookies.Value + "<br/>");
                }
            }
         
        }

/////********************************************************************
修改cookie
1 Response.Cookies["Info"]["user"] = "2";
2 Response.Cookies["Info"].Expires = DateTime.Now.AddDays(1);        删除cookie下的属性
1 HttpCookie acookie=Request.Cookies["Info"];
2 acookie.Values.Remove("userid");
3 acookie.Expires = DateTime.Now.AddDays(1);
4 Response.Cookies.Add(acookie);        删除所有cookie，就是设置过期时间为现在就行了
1 int limit=Request.Cookies.Count - 1;
2 for(int i=0;i<limit;i++)
3 {
4     acookie = Request.Cookies(i)
5     acookie.Expires = DateTime.Now.AddDays(-1)
6     Response.Cookies.Add(acookie)
7 }        这下不用到处找了