引用借以记录借鉴 实现记住密码和自动登录功能

WEB页面代码：

            <form id="Form1" runat="server">
            <input type="hidden" id="hidPass" runat="server" />
            <input type="text" runat="server" id="txtLoginName" />
            <asp:TextBox runat="server" ID="txtPassWord" class="textwidthheigh" TextMode="Password"></asp:TextBox>
            <input type="checkbox" runat="server" value="记住密码" id="chkRemember" onclick="CheckRemember()" />
            <input type="checkbox" runat="server" value="自动登录" id="chkLogin" onclick="CheckLogin()" />
            <asp:Button runat="server"  id="btnLogin"  onclick="btnLogin_Click"  />
            <input type="button" id="btnClear" onclick="Clear()"  />
            </form>
            <script type="text/javascript" language="javascript">
            //页面加载用户名输入框获得焦点
            document.getElementById("txtLoginName").focus();
            function Clear() {
            //用户点击取消，清空用户名和用户密码
            document.getElementById("txtLoginName").value = "";
            document.getElementById("txtPassWord").value = "";
            }
            function CheckLogin() {
            //用户勾选自动登录时，把记住密码也勾选上
            var remember = document.getElementById("chkRemember");
            remember.checked = true;
            }
            function CheckRemember() {
            var remenber = document.getElementById("chkRemember");
            var login = document.getElementById("chkLogin");
            if (remenber.checked == false) {
            login.checked = false;
            //用户去掉记住密码时，也把自动登录去掉
            }
            }
        
            </script>

后台代码：

 protected void Page_Load(object sender, EventArgs e)
        {
            if (!IsPostBack)
            {
                //获取客户端的Cookies，分别两个cookies，一个登陆名，一个密码
                HttpCookie LoginNameCookie = Request.Cookies["Bic_LoginName"];
                HttpCookie LoginPassCookie = Request.Cookies["Bic_Pass"];
                if (LoginNameCookie != null)
                {
                    //登录名的cookies不为空，填充登陆名
                    txtLoginName.Value = LoginNameCookie.Value;
                }
                if (LoginPassCookie != null)
                {
                    //密码cookies不为空，给密码框和隐藏密码框填充，当然我们的密码是加密过才存到cookies去的，至于以藏文本框的作用后面就会看到
                    this.txtPassWord.Attributes.Add("value", LoginPassCookie.Value + "");
                    hidPass.Value = LoginPassCookie.Value + "";//赋值给隐藏控件
                    chkRemember.Checked = true;
                }
                //获取是否有勾选自动登录的cookies
                HttpCookie Login = Request.Cookies["Bic_LoginAuto"];
                //当用户在系统点击退出时
                if (Request["opFlag"] == "Exit")
                {
                    this.txtPassWord.Attributes.Add("value", "");//把密码去掉
                    chkRemember.Checked = false;//记住密码去掉
                    HttpCookie loginNameCookie = Request.Cookies["Bic_LoginName"];//获取登录名cookies
                    HttpCookie loginPassCookie = Request.Cookies["Bic_Pass"];//获取密码cookies
                    if (loginNameCookie != null)
                    {
                        //把cookies时间设为-2相当于删掉了cookies
                        loginNameCookie.Expires = DateTime.Now.AddDays(-2);
                        Response.Cookies.Set(loginNameCookie);
                    }
                    if (loginPassCookie != null)
                    {
                        //把密码的cookies也删掉
                        loginPassCookie.Expires = DateTime.Now.AddDays(-2);
                        Response.Cookies.Set(loginPassCookie);
                    }
                    //自动登录cookies也一样
                    HttpCookie login = Request.Cookies["Bic_LoginAuto"];
                    if (login != null)
                    {
                        login.Expires = DateTime.Now.AddDays(-2);
                        Response.Cookies.Set(login);
                    }
                }
                else//用户打开登录界面时
                {
                    //自动登录cookies不为空，用户名不为空，隐藏框密码不为空
                    if (Login != null && txtLoginName.Value != "" && hidPass.Value != "")
                    {
                        SysUser user = new SysUser();
                        user.Login_Name = txtLoginName.Value;
                        user.Login_Pass = hidPass.Value;
                        int i = SysUserBLL.Login(user);//验证登录
                        if (i > 0)
                        {
                            //成功登录跳转到default.aspx页面
                            Page.Session["Login_Name"] = user.Login_Name;
                            HttpContext.Current.Session["Display_Name"] = SysUserBLL.getDisplayNameByname(user.Login_Name);
                            Response.Write("<script>window.location='Default.aspx';</script>");
                            Response.End();
                        }
                    }
                }
            }
        }
        //点击登录按钮事件
        protected void btnLogin_Click(object sender, EventArgs e)
        {
            //判断是否为空
            if (txtLoginName.Value.Trim() != "" && txtPassWord.Text.Trim() != "")
            {
                SysUser user = new SysUser();
                user.Login_Name = txtLoginName.Value.Trim();
                user.Login_Pass = CommonHelper.MD5encipher(txtPassWord.Text.Trim());//MD5加密
                HttpCookie LoginNameCookie = Request.Cookies["Bic_LoginName"];
                HttpCookie LoginPassCookie = Request.Cookies["Bic_Pass"];
                if (LoginNameCookie != null)//如果是记住密码情况
                {
                    if (txtLoginName.Value.Trim() == LoginNameCookie.Value.Trim())//读取到cookies保存的用户名和文本框用户名相同，预防用户又改动
                    {
                        if (LoginPassCookie != null)
                        {
                            if (txtPassWord.Text.Trim() == LoginPassCookie.Value.Trim())//cookies读取到的密码和文本框密码相同
                            {
                                user.Login_Pass = txtPassWord.Text.Trim();
                            }

                        }
                    }
                }
                int i = SysUserBLL.Login(user);//验证登录
                if (i > 0)
                {
                    if (chkRemember.Checked == true)//记住密码
                    {
                        HttpCookie loginNameCookie = new HttpCookie("Bic_LoginName", user.Login_Name);
                        HttpCookie loginPassCookie = new HttpCookie("Bic_Pass", user.Login_Pass);
                        loginPassCookie.Expires = DateTime.Now.AddDays(1);
                        loginNameCookie.Expires = DateTime.Now.AddDays(1);
                        Response.Cookies.Add(loginNameCookie);
                        Response.Cookies.Add(loginPassCookie);
                        if (chkLogin.Checked == true)//自动登录 
                        {
                            HttpCookie Login = new HttpCookie("Bic_LoginAuto", "true");
                            Login.Expires = DateTime.Now.AddDays(1);
                            Response.Cookies.Add(Login);
                        }
                        else
                        {
                            HttpCookie Login = Request.Cookies["Bic_LoginAuto"];
                            if (Login != null)
                            {
                                Login.Expires = DateTime.Now.AddDays(-2);
                                Response.Cookies.Set(Login);
                            }
                        }
                    }
                    else//没选记住密码
                    {
                        HttpCookie loginNameCookie = Request.Cookies["Bic_LoginName"];
                        HttpCookie loginPassCookie = Request.Cookies["Bic_Pass"];
                        if (loginNameCookie != null)
                        {
                            loginNameCookie.Expires = DateTime.Now.AddDays(-2);
                            Response.Cookies.Set(loginNameCookie);
                        }
                        if (loginPassCookie != null)
                        {
                            loginPassCookie.Expires = DateTime.Now.AddDays(-2);
                            Response.Cookies.Set(loginPassCookie);
                        }
                    }
                    Page.Session["Login_Name"] = user.Login_Name;
                    HttpContext.Current.Session["Display_Name"] = SysUserBLL.getDisplayNameByname(user.Login_Name);
                    Response.Write("<script>window.location='Default.aspx';</script>");
                }
                else
                {
                    Response.Write("<script>alert('用户名或密码错误!');window.location='Login.aspx';</script>");
                }
            }
            else
            {
                Response.Write("<script>alert('请输入账号和密码!');window.location='Login.aspx';</script>");
            }
        }