系统登录详解

    @using (Html.BeginForm("Login", "Account", FormMethod.Post))
    {
        <div class="login_position">
            <p class="center_text p1 top30_M">xx平台管理</p>
            <div class="hr1"></div>
            <div class="left50_M">
                <div class="login_input top15_M">
                    <img src="~/Content/images/login_person.png" /><input type="text" name="username" autocomplete="off" id="username" placeholder="请输入用户名" />
                </div>
                <div class="login_input top30_M">
                    <img src="~/Content/images/login_lock.png" /><input type="password" name="password" placeholder="请输入密码"/>
                </div>
                <div class="top30_M">
                <input placeholder="验证码" name="code" autocomplete="off" id="code" class="login_input2" style="width:100px;" />
                    <img class="left15_M" onclick="this.src = this.src + ‘?‘ + Math.random();" src="@Url.Action("code","Account")" title="看不清楚,换一张" width="83" height="29" align="absmiddle" style="cursor: pointer;" id="imgcodeaa" />
                </div>
                <input type="submit" value="登     录" class="login_btn top30_M" />
            </div>
        </div>
    }

        //验证码入口
        [AllowAnonymous]
        public ActionResult Code()
        {
            return File(AccountController.CreateCheckIamge(), @"iamge/Jpeg");
        }

        //验证码生成并且存入服务器session
        private static string GenerateCheckCode()
        {
            try
            {
                int number;
                char code;
                string checkCode = String.Empty;

                System.Random random = new Random();

                for (int i = 0; i < 4; i++)
                {
                    number = random.Next();

                    if (number % 2 == 0)
                        code = (char)(‘0‘ + (char)(number % 10));
                    else
                        code = (char)(‘A‘ + (char)(number % 26));

                    checkCode += code.ToString();
                }

                //Session["CheckCode"] = checkCode;
                System.Web.HttpContext.Current.Session.Add("CheckCode", checkCode.ToLower());
                //Response.Cookies.Add(new HttpCookie("CheckCode", checkCode));       

                return checkCode;
            }
            catch (Exception ex)
            {

                return "";
            }
        }

        //添加水印
        private static byte[] CreateCheckCodeImage(string checkCode)
        {
            if (checkCode == null || checkCode.Trim() == String.Empty)
                return null;

            System.Drawing.Bitmap image = new System.Drawing.Bitmap((int)Math.Ceiling((checkCode.Length * 12.5)), 22);
            Graphics g = Graphics.FromImage(image);

            try
            {
                //生成随机生成器
                Random random = new Random();

                //清空图片背景色
                g.Clear(Color.White);

                //画图片的背景噪音线
                for (int i = 0; i < 25; i++)
                {
                    int x1 = random.Next(image.Width);
                    int x2 = random.Next(image.Width);
                    int y1 = random.Next(image.Height);
                    int y2 = random.Next(image.Height);

                    g.DrawLine(new Pen(Color.Silver), x1, y1, x2, y2);
                }

                Font font = new System.Drawing.Font("Arial", 12, (System.Drawing.FontStyle.Bold | System.Drawing.FontStyle.Italic));
                System.Drawing.Drawing2D.LinearGradientBrush brush = new System.Drawing.Drawing2D.LinearGradientBrush(new Rectangle(0, 0, image.Width, image.Height), Color.Blue, Color.DarkRed, 1.2f, true);
                g.DrawString(checkCode, font, brush, 2, 2);

                //画图片的前景噪音点
                for (int i = 0; i < 100; i++)
                {
                    int x = random.Next(image.Width);
                    int y = random.Next(image.Height);

                    image.SetPixel(x, y, Color.FromArgb(random.Next()));
                }

                //画图片的边框线
                g.DrawRectangle(new Pen(Color.Silver), 0, 0, image.Width - 1, image.Height - 1);

                System.IO.MemoryStream ms = new System.IO.MemoryStream();
                image.Save(ms, System.Drawing.Imaging.ImageFormat.Gif);
                //Response.ClearContent();
                //Response.ContentType = "image/Gif";
                //Response.BinaryWrite(ms.ToArray());
                return ms.ToArray();
            }
            finally
            {
                g.Dispose();
                image.Dispose();
            }
        }

        public static byte[] CreateCheckIamge()
        {
            return CreateCheckCodeImage(GenerateCheckCode());
        }

[HttpPost]
        [AllowAnonymous]
        public ActionResult Login(FormCollection fc)
        {
            return base.Visit(() =>
            {
                string username = fc["username"];
                string password = fc["password"];
                if (!string.IsNullOrEmpty(username))
                {
                    //获取表单数据
                    if (Session["CheckCode"] == null)
                    {
                        throw new Exception("获取验证码时失败，请确认您是否关闭浏览器 cookie 功能");
                    }
                    string code = Request["code"].ToLower().Trim();
                    string checkcode = Session["CheckCode"].ToString().ToLower().Trim();
                    if (code != checkcode)
                    {
                        return Content("<script>alert(‘验证码输入错误!请重新输入验证码！‘);window.location.href=‘/Account/Login‘</script>");
                    }

                    var model = BLL.Sys.AccountBLL.Instance.GetModel(username, password);
                    if (model == null)
                    {
                        return Content("<script>alert(‘用户名或密码错误！‘);window.location.href=‘/Account/Login‘</script>");
                    }
                    else
                    {
                        //提供对票证的属性和值的访问，这些票证用于 Forms 身份验证对用户进行标识,绑定用户名
                        FormsAuthenticationTicket ticket = new FormsAuthenticationTicket(username, false, (int)FormsAuthentication.Timeout.TotalMinutes);
                        //加密HTTP Cookie 中的 Forms 身份验证票证
                        string enticket = FormsAuthentication.Encrypt(ticket);
                        // 创建和命名新的 Cookie，并为其赋值。
                        HttpCookie cookieofau = new HttpCookie(FormsAuthentication.FormsCookieName, enticket);
                        //HTTP Cookie 添加到 HTTP 响应 Cookie 集合
                        Response.AppendCookie(cookieofau);
                        return RedirectToAction("index", "Home");
                    }
                }
                return View();
            });
        }

public ActionResult LogOut()
        {
            return base.Visit(() =>
            {
                //查看是否为已经验证的客户
                if (User.Identity.IsAuthenticated)
                {
                    //获取客户端发送的 Cookie 的集合, Forms 身份验证票证的 Cookie 名称。默认值是“.ASPXAUTH”。
                    HttpCookie authcookie = Request.Cookies[FormsAuthentication.FormsCookieName];
                    //获取 FormsAuthenticationTicket对象 （传值为加密的 票据表示）
                    FormsAuthenticationTicket ticket = FormsAuthentication.Decrypt(authcookie.Value);
                    //从浏览器删除 Forms 身份验证票证。
                    FormsAuthentication.SignOut();
                }
                return Redirect("/Account/Login");
            });
        }

<!DOCTYPE html>

<html lang="en" xmlns="http://www.w3.org/1999/xhtml">
<head>
    <meta charset="utf-8" />
    <title></title>
    <script src="jquery-3.3.1.js"></script>
    <style>
        body{
    background: #999;
}
#divID {
        position: fixed;
        left: 47%;
        top: 53%;
        width: 500px;
        margin-left: -200px;
        margin-top: -150px;
        font-family: "黑体";
        /*禁止复制粘贴*/
        -moz-user-select: none;
        -webkit-user-select: none;
        user-select:none;
        color:#fff;
    }
    .register_dialog_info {
        float: left;
        margin-left:10px;
        color: #fff;
        margin-top: 5px;
        font-size: 20px;
    }
    form{padding: 20px 0px;}
    ul li {list-style: none;}
    .sub {
        text-align: center;
    }
    .sub input {
        display: inline-block;
        width: 300px;
        background-color: #999;
        color: rgb(255, 255, 255);
        font-size: 20px;
        text-align: center;
        height: 40px;
        line-height: 40px;
        font-family: 黑体;
        outline: none;
        border: none;
        margin: auto;
        border-radius: 10px;
    }
    input[type = "submit"]:hover{cursor: pointer;}

    .reg-box { padding-left: 30px; }

    .reg-box li { line-height: 44px; width: 500px; overflow: hidden; }

    .reg-box li label { width: 68px; height: 50px; float: left; line-height: 50px; text-align: right; padding-right: 20px; }

    .reg-box li input,.reg-box li select{ border-radius: 3px; padding: 6px 0; font-size: 16px; width: 296px; height: 49px; line-height: 28px; border: 1px solid #dddddd; text-indent: 0.5em; float: left; }

    .reg-box li select option{font-size:16px;}

    /*验证码*/
    .add { width: 128px; height: 44px; float: left; _display: inline; cursor: pointer; margin-left: 20px; }

    .reg-box li .sradd { width: 148px; text-indent: 4px; font-size: 14px; }

    .reg-box li .input-code { width: 106px; padding: 10px; font-family: Arial; font-style: italic; color: red; letter-spacing: 1px; cursor: pointer; text-align: center; text-indent: 0; }

    .yzm,.phoKey { background: #012246; text-align: center; line-height: 44px; color: #fff; border-radius: 3px;}

    .phoKey{letter-spacing: 3px; font-size:18px;}

    .yzmc { background: #dddddd; text-align: center; line-height: 44px; color: #999; }

    .error { clear:both;display:block;color: red; padding-left: 90px; padding-bottom:5px;height:20px;float: left; font-size:12px;line-height: 20px;}

    input { background-color: #fff; outline: none; }

    .reg-box li { width: auto; }

    .reg-box li input.errorC, .errorC{ border: 1px solid blue; }

    .reg-box li input.checkedN , .checkedN{ border: 1px solid #1ece6d; }
    </style>
    <script>
        //文本框默认提示文字
        function textFocus(el) {
            if (el.defaultValue == el.value) { el.value = ‘‘; el.style.color = ‘#333‘; }
        }
        function textBlur(el) {
            if (el.value == ‘‘) { el.value = el.defaultValue; el.style.color = ‘#999‘; }
        }

        $(function () {
            /*生成验证码*/
            create_code();

            //登录页面的提示文字
            //账户输入框失去焦点
            (function login_validate() {
                $(".reg-box .account").blur(function () {
                    //reg=/^1[3|4|5|8][0-9]\d{4,8}$/i;//验证手机正则(输入前7位至11位)

                    if ($(this).val() == "" || $(this).val() == "请输入您的账号") {
                        $(this).addClass("errorC");
                        $(this).next().html("账号不能为空！");
                        $(this).next().css("display", "block");
                        $(".sub input").prop(‘disabled‘, true);
                    }
                        //                else if($(".reg-box .account").val().length<11)
                        //                {
                        //                    $(this).addClass("errorC");
                        //                    $(this).next().html("账号长度有误！");
                        //                    $(this).next().css("display","block");
                        //                }
                        //                else if(!reg.test($(".reg-box .account").val()))
                        //                {
                        //                    $(this).addClass("errorC");
                        //                    $(this).next().html("账号不存在!");
                        //                    $(this).next().css("display","block");
                        //                }
                    else {
                        $(".sub input").prop(‘disabled‘, false);
                        $(this).addClass("checkedN");
                        $(this).removeClass("errorC");
                        $(this).next().empty();
                    }
                });
                /*密码输入框失去焦点*/
                $(".reg-box .admin_pwd").blur(function () {
                    //reg=/^[\@A-Za-z0-9\!\#\$\%\^\&\*\.\~]{6,22}$/;

                    if ($(this).val() == "") {
                        $(this).addClass("errorC");
                        $(this).next().html("密码不能为空！");
                        $(this).next().css("display", "block");
                        $(".sub input").prop(‘disabled‘, true);
                    }
                        //                else if(!reg.test($(".admin_pwd").val())) {
                        //                    $(this).addClass("errorC");
                        //                    $(this).next().html("密码为6~12位的数字、字母或特殊字符！");
                        //                    $(this).next().css("display","block");
                        //                }
                    else {
                        $(".sub input").prop(‘disabled‘, false);
                        $(this).addClass("checkedN");
                        $(this).removeClass("errorC");
                        $(this).next().empty();
                    }
                });

                /*验证码输入框失去焦点*/
                $(".reg-box .photokey").blur(function () {
                    var code1 = $(‘.reg-box input.photokey‘).val().toLowerCase();
                    var code2 = $(".reg-box .phoKey").text().toLowerCase();
                    if (code1 != code2) {
                        $(this).addClass("errorC");
                        $(this).next().next().html("验证码输入错误!!!");
                        $(this).next().next().css("display", "block");
                        $(".sub input").prop(‘disabled‘, true);
                    }
                    else {
                        $(".sub input").prop(‘disabled‘, false);
                        $(this).removeClass("errorC");
                        $(this).next().next().empty();
                        $(this).addClass("checkedN");
                    }
                })
            })();
        });
        function create_code() {
            function shuffle() {
                var arr = [‘1‘, ‘r‘, ‘Q‘, ‘4‘, ‘S‘, ‘6‘, ‘w‘, ‘u‘, ‘D‘, ‘I‘, ‘a‘, ‘b‘, ‘c‘, ‘d‘, ‘e‘, ‘f‘, ‘g‘, ‘h‘, ‘i‘, ‘j‘, ‘k‘, ‘l‘, ‘m‘, ‘n‘, ‘o‘, ‘p‘,
                    ‘q‘, ‘2‘, ‘s‘, ‘t‘, ‘8‘, ‘v‘, ‘7‘, ‘x‘, ‘y‘, ‘z‘, ‘A‘, ‘B‘, ‘C‘, ‘9‘, ‘E‘, ‘F‘, ‘G‘, ‘H‘, ‘0‘, ‘J‘, ‘K‘, ‘L‘, ‘M‘, ‘N‘, ‘O‘, ‘P‘, ‘3‘, ‘R‘,
                    ‘5‘, ‘T‘, ‘U‘, ‘V‘, ‘W‘, ‘X‘, ‘Y‘, ‘Z‘];
                return arr.sort(function () {
                    return (Math.random() - .5);
                });
            };
            shuffle();
            function show_code() {
                var ar1 = ‘‘;
                var code = shuffle();
                for (var i = 0; i < 6; i++) {
                    ar1 += code[i];
                }
                ;
                //var ar=ar1.join(‘‘);
                $(".reg-box .phoKey").text(ar1);
            };
            show_code();
            $(".reg-box .phoKey").click(function () {
                show_code();
            });
        }
    </script>
</head>
<body>
    <div id="divID">
        <div style="background-color:transparent;">
            <form id="ff" method="post">
                <ul class="reg-box">
                    <li>
                        <label for="">账    号</label>
                        <input type="text" name="accName" value="" class="account" maxlength="11" style="color:#999;" onblur="textBlur(this)" onfocus="textFocus(this)" />
                        <span class="error error5"></span>
                    </li>
                    <li>
                        <label for="">密    码</label>
                        <input type="password" name="accPassWord" class="admin_pwd" value="" style="color:#999;" onblur="textBlur(this)" onfocus="textFocus(this)" />
                        <span class="error error6"></span>
                    </li>
                    <li>
                        <label for="">验证码</label>
                        <input type="text" class="sradd photokey" id="key" value="" style="color:#999;ime-mode:disabled;-webkit-ime-mode:inactive;" onblur="textBlur(this)" onfocus=" textFocus(this) " />
                        <span class="add phoKey"></span>
                        <span class="error error7"></span>
                    </li>
                </ul>
                <div class="sub">
                    <input type="submit" value="立即登录" />
                </div>
            </form>
        </div>
    </div>
</body>
</html>