自动登录、记住我（保存登陆状态）实现：
保存在客户端
不能用session，可以用cookies保存
实现方式：
面加载读取Cookie判断，正确写入Session,转向
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
if (Request.Cookies["cUser"] != null Request.Cookies["cPwd"] != null)
{
string cUser = Request.Cookies["cUser"].Value;
string cPwd = Request.Cookies["cPwd"].Value;
string sqlPwd = "";
BookShop.Model.User oneUser = bll.Exists(cUser);
if (oneUser != null)
{
#region MyRegion
//说明存在cUser
if (cPwd.Length 2)//防止用户修改Cookie中的密码报错
{
string salt = cPwd.Substring(0, 2);
sqlPwd = oneUser.LoginPwd;
sqlPwd = Encrypt(sqlPwd, salt);
if (cPwd == sqlPwd)
{
//保存Session状态
Session["user"] = oneUser;
//转向
#region MyRegion
if (Request.QueryString["returnUrl"] == null)
{
//登陆成功，转向首页
Response.Redirect("/member/ShowMessage.aspx?returnUrl=" + Server.UrlEncode("/Default.aspx") + " msg=" + Server.UrlEncode("自动登陆成功") + " txt=" + Server.UrlEncode("转向首页"));
}
else
{
//登陆成功，转向上次访问页面
string returnUrl = Request.QueryString["returnUrl"];
Response.Redirect(returnUrl);
}
#endregion
}
}
#endregion
}
//如果Cookies出错...清除cookie
ClearLoginCookie();
}
}
}
//页面登陆
protected void btnLogin_Click(object sender, ImageClickEventArgs e)
{
if (!Page.IsValid)
{
return;
}
string uid = txtLoginId.Text.Trim();
string pwd = txtLoginPwd.Text.Trim();
BookShop.Model.User oneUser;
UserManager bll = new UserManager();
bool result = bll.Login(uid, pwd, out oneUser);
if (result)
{
//保存session
Session["user"] = oneUser;
//保存Cookie状态
if (cbAutoLogin.Checked)
{
HttpCookie cUser = new HttpCookie("cUser", uid);
HttpCookie cPwd = new HttpCookie("cPwd", Encrypt(oneUser.LoginPwd));
cUser.Expires = DateTime.Now.AddYears(10);
cPwd.Expires = DateTime.Now.AddYears(10);
Response.Cookies.Add(cUser);
Response.Cookies.Add(cPwd);
}
if (Request.QueryString["returnUrl"] == null)
{
//登陆成功，转向首页
Response.Redirect("/Default.aspx");
}
else
{
//登陆成功，转向上次访问页面
string returnUrl = Request.QueryString["returnUrl"];
Response.Redirect("/member/ShowMessage.aspx?returnUrl=" + HttpContext.Current.Server.UrlEncode(returnUrl) + " msg=" + Server.UrlEncode("登陆成功") + " txt=" + Server.UrlEncode("转向上次访问页面"));
}
}
else
{
//登陆失败，提示错误信息
Page.ClientScript.RegisterStartupScript(this.GetType(), Guid.NewGuid().ToString(), "alert('用户名或密码错误！');", true);
}
}
/// summary
/// 对密码进行MD5加密
/// /summary
/// param /param
/// returns /returns
protected string Encrypt(string pwd)
{
return Encrypt(pwd, null);
}
/// summary
/// MD5加密方法扩展
/// /summary
/// param /param
/// returns /returns
protected string Encrypt(string pwd, string salt)
{
//加密规则: salt+md5(salt+md5(pwd+"zfx"))
MD5 md5 = MD5.Create();//MD5加密方法
byte[] buffer = System.Text.Encoding.UTF8.GetBytes(pwd + "zfx");
buffer = md5.ComputeHash(buffer);
string str = "";
for (int i = 0; i buffer.Length; i++)
{
str += buffer[i].ToString("X2");
}
if (salt == null)
{
Random r = new Random();
salt = ((char)(r.Next(65, (65 + 26)))).ToString() + ((char)(r.Next(65, (65 + 26)))).ToString();
}
str = salt + str;
str = CommenCodes.CommenCodes.Md5(str); //调用其他类库中 MD5实现方法，具体实现见本方法之前
return (salt + str);
}
/// summary
/// （在服务器端）清除客户端cookie
/// /summary
private void ClearLoginCookie()
{
//在服务器端清除客户端cookie
HttpCookie cUser = new HttpCookie("cUser");//新建两个跟之前同名的cookie,用于覆盖客户端的cookie
HttpCookie cPwd = new HttpCookie("cPwd");
cUser.Expires = DateTime.Now.AddYears(-10);//设置过期时间为过期
cPwd.Expires = DateTime.Now.AddYears(-10);
Response.Cookies.Add(cUser);
Response.Cookies.Add(cPwd);
}
自动登录绝对不安全，有安全隐患
进入网站后，对于关键步骤再次要求用户输入密码