cookie来记录密码

if (CheckBox1.Checked)
  {//记住密码
          System.Web.HttpCookie newcookie = new HttpCookie("user");
           newcookie.Values["username"] = username.Text;
           newcookie.Values["password"] = sPwd;
           newcookie.Expires = DateTime.Now.AddDays(15);
           Response.AppendCookie(newcookie);
 }
else
{
          if (Request.Cookies["user"] != null)
          {
                Request.Cookies["user"].Expires = DateTime.Now.AddDays(-1);
                Request.Cookies.Clear();
           }
}

读取密码：

 if (Request.Cookies["user"] != null)
                    {
                        String sPwd = Request.Cookies["user"]["password"].ToString();
                       // sPwd = LsqCrypt.decrypt(sPwd);
                        pwd.Attributes["value"] = sPwd;
                        username.Text = Request.Cookies["user"]["username"].ToString();
                        CheckBox1.Checked = true;
                    }

 

实际运用时密码和用户名是要加密的，但疑惑的是用 Request.Cookies["user"].Expires = DateTime.Now.AddDays(-1);设置Cookies失效好像没用,clear也没用

if (CheckBox1.Checked)
{//记住密码
System.Web.HttpCookie newcookie = new HttpCookie("user");
newcookie.Values["username"] = username.Text;
newcookie.Values["password"] = sPwd;
newcookie.Expires = DateTime.Now.AddDays(15);
Response.AppendCookie(newcookie);
}
else
{
System.Web.HttpCookie cookie = Request.Cookies["user"];
if (cookie != null)
{
cookie.Expires = DateTime.Now.AddDays(-2);
Response.Cookies.Set(cookie);

}
}