一用户 
1.1用户注册 
1.2用户登陆 

首先在Models里添加用户登陆模型类UserLogin，该类只要用用户名，密码和验证码三个字段。 

/// <summary>
 /// 用户登陆模型
 /// </summary>
 public class UserLogin
 {
 /// <summary>
 /// 用户名
 /// </summary>
 [Display(Name = "用户名", Description = "4-20个字符。")]
 [Required(ErrorMessage = "×")]
 [StringLength(20, MinimumLength = 4, ErrorMessage = "×")]
 public string UserName { get; set; }
 /// <summary>
 /// 密码
 /// </summary>
 [Display(Name = "密码", Description = "6-20个字符。")]
 [Required(ErrorMessage = "×")]
 [StringLength(20, MinimumLength = 6, ErrorMessage = "×")]
 [DataType(DataType.Password)]
 public string Password { get; set; }
 /// <summary>
 /// 验证码
 /// </summary>
 [Display(Name = "验证码", Description = "请输入图片中的验证码。")]
 [Required(ErrorMessage = "×")]
 [StringLength(6, MinimumLength = 6, ErrorMessage = "×")]
 public string VerificationCode { get; set; }

 }

在UserController里添加Login action； 代码看如下：

public ActionResult Login()
 {
 return View();
 }
 [HttpPost]
 public ActionResult Login(UserLogin login)
 {
 return View();
 }

使用Cookie保存登陆账号，密码等信息，修改public ActionResult Login(UserLogin login)。修改完成代码如下：

[HttpPost]
 public ActionResult Login(UserLogin login)
 {
 //验证验证码
 if (Session["VerificationCode"] == null || Session["VerificationCode"].ToString() == "")
 {
 Error _e = new Error { Title = "验证码不存在", Details = "在用户注册时，服务器端的验证码为空，或向服务器提交的验证码为空", Cause = "<li>你注册时在注册页面停留的时间过久页已经超时</li><li>您绕开客户端验证向服务器提交数据</li>", Solution = "返回<a href='" + Url.Action("Register", "User") + "'>注册</a>页面，刷新后重新注册" };
 return RedirectToAction("Error", "Prompt", _e);
 }
 else if (Session["VerificationCode"].ToString() != login.VerificationCode.ToUpper())
 {
 ModelState.AddModelError("VerificationCode", "×");
 return View();
 }
 //验证账号密码
 userRsy = new UserRepository();
 if (userRsy.Authentication(login.UserName, Common.Text.Sha256(login.Password)) == 0)
 {
 HttpCookie _cookie = new HttpCookie("User");
 _cookie.Values.Add("UserName", login.UserName);
 _cookie.Values.Add("Password", Common.Text.Sha256(login.Password));
 Response.Cookies.Add(_cookie);
 return RedirectToAction("Default","User");
 }
 else
 {
 ModelState.AddModelError("Message", "登陆失败！");
 return View();
 }

 }

在public ActionResult Login() 上右键添加强类型视图

完成后代的Login.cshtml 

@model CMS.Models.UserLogin

@{
 ViewBag.Title = "用户登陆";
 Layout = "~/Views/Shared/_Layout.cshtml";
}
 
<div class="banner"> 
 <img src="~/Skins/Default/Images/banner.jpg" /> 
</div>
 

@using (Html.BeginForm()) 
{ 
 @Html.ValidationSummary(true)

 <div class="form"> 
 <dl> 
 <dt>用户登陆</dt> 
 <dd> 
 <div class="label">@Html.LabelFor(model => model.UserName)：</div> 
 <div class="ctrl">@Html.EditorFor(model => model.UserName) 
 @Html.ValidationMessageFor(model => model.UserName) 
 @Html.DisplayDescriptionFor(model => model.UserName) 
 </div> 
 </dd> 
 <dd> 
 <div class="label">@Html.LabelFor(model => model.Password)：</div> 
 <div class="ctrl">@Html.PasswordFor(model => model.Password) 
 @Html.ValidationMessageFor(model => model.Password) 
 @Html.DisplayDescriptionFor(model => model.Password) 
 </div> 
 </dd> 
 <dd> 
 <div class="label">验证码：</div> 
 <div class="ctrl">
 @Html.TextBoxFor(model => model.VerificationCode) 
 @Html.ValidationMessageFor(model => model.VerificationCode) 
 <img id="verificationcode" alt="" src="@Url.Action("VerificationCode", "User")" /> 
 <a id="trydifferent" style="cursor: pointer">换一张</a> 
 </div> 
 </dd> 
 <dd> 
 <div class="label"></div> 
 <div class="ctrl"> 
 <input type="submit" value="登陆" />@Html.ValidationMessage("Message"); 
 </div> 
 </dd> 
 </dl> 
 <div class="clear"></div> 
 </div>
}

<script type="text/javascript">
 $("#trydifferent").click(function () { 
 $("#verificationcode").attr("src", "/User/VerificationCode?" + new Date()); 
 })

</script>
@section Scripts { 
 @Scripts.Render("~/bundles/jqueryval") 
}

浏览器中查看一下登陆页面

点下登陆测试一下。OK登陆成功 

验证用户是否已经登陆，这块和权限验证一起从AuthorizeAttribute继承个自定义验证类 

在项目里添加Extensions文件夹，添加一个类UserAuthorizeAttribute 继承自AuthorizeAttribute，重写AuthorizeCore方法用来实现用户是否已经登陆的验证，权限验证在写权限功能时在补充 

using Ninesky.Repository;

namespace System.Web.Mvc
{
 /// <summary>
 /// 用户权限验证
 /// </summary>
 public class UserAuthorizeAttribute :AuthorizeAttribute
 {
 /// <summary>
 /// 核心【验证用户是否登陆】
 /// </summary>
 /// <param name="httpContext"></param>
 /// <returns></returns>
 protected override bool AuthorizeCore(HttpContextBase httpContext)
 {
 //检查Cookies["User"]是否存在
 if (httpContext.Request.Cookies["User"] == null) return false;
 //验证用户名密码是否正确
 HttpCookie _cookie = httpContext.Request.Cookies["User"];
 string _userName = _cookie["UserName"];
 string _password = _cookie["Password"];
 httpContext.Response.Write("用户名:"+_userName);
 if (_userName == "" || _password == "") return false;
 UserRepository _userRsy = new UserRepository();
 if (_userRsy.Authentication(_userName, _password) == 0) return true;
 else return false;
 }
 }
}

以后只要在需要登陆后才能操作的Action或Controller上加[UserAuthorize]就可实现验证是否已经登录了。
退出功能，在UserController添加Logout Action 

/// <summary>
 /// 退出系统
 /// </summary>
 /// <returns></returns>
 public ActionResult Logout()
 {
 if (Request.Cookies["User"] != null)
 {
 HttpCookie _cookie = Request.Cookies["User"];
 _cookie.Expires = DateTime.Now.AddHours(-1);
 Response.Cookies.Add(_cookie);
 }
 Notice _n = new Notice { Title = "成功退出", Details = "您已经成功退出！", DwellTime = 5, NavigationName="网站首页", NavigationUrl = Url.Action("Index", "Home") };
 return RedirectToAction("Notice", "Prompt", _n);
 }