asp.Net Cookie相關知識

//寫入
    protected void Button2_Click(object sender, EventArgs e)
    {
        HttpCookie cookie=new HttpCookie("MyCook");//初使化並設定Cookie的名稱
        DateTime dt=DateTime.Now;
        TimeSpan ts = new TimeSpan(0, 0, 1,0,0);//到期時間為1分鐘
        cookie.Expires = dt.Add(ts);//設定到期時間
        cookie.Values.Add("userid", "userid_value");
        cookie.Values.Add("userid2","userid2_value2");
        Response.AppendCookie(cookie);
        //輸出該Cookie的所有內容
        //Response.Write(cookie.Value); //輸出為：userid=userid_value&userid2=userid2_value2 
    }

    //讀取
    protected void Button1_Click(object sender, EventArgs e)
    {

       // HttpCookie cokie = new HttpCookie("MyCook");//初使化
        if (Request.Cookies["MyCook"]!=null)
        {
            //Response.Write("Cookie中索引值為userid的值:" + Request.Cookies["MyCook"]["userid"]);//整行
            //Response.Write("Cookie中索引值為userid2的值" + Request.Cookies["MyCook"]["userid2"]);
            Response.Write(Request.Cookies["MyCook"].Value);//輸出全部的值
        }
    }

    //修改Cookie
    protected void Button3_Click(object sender, EventArgs e)
    {
        //擷取用戶端的Cookie對象
        HttpCookie cok = Request.Cookies["MyCook"];
        
        if (cok != null)
        {
         //修改Cookie的兩種方法
            cok.Values["userid"] = "alter-value";
            cok.Values.Set("userid", "alter-value");

          //往Cookie裡加入新的內容
             cok.Values.Set("newid", "newValue");
             Response.AppendCookie(cok);
        }

      
    }
    //刪除Cookie
    protected void Button4_Click(object sender, EventArgs e)
    {

        HttpCookie cok = Request.Cookies["MyCook"];
        if (cok != null)
        {
            if (!CheckBox1.Checked)
            {
                cok.Values.Remove("userid");//移除索引值為userid的值
            }
            else
            {
                TimeSpan ts = new TimeSpan(-1, 0, 0, 0);
                cok.Expires = DateTime.Now.Add(ts);//刪除整個Cookie，只要把到期時間設定為現在
            }
            Response.AppendCookie(cok);
        }
    }