ASP.NET MVC 实现统一登录验证

Love The Way You Lie 2022-05-31 05:06 156阅读 0赞

1.先写个主页面

using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Web;
    using System.Web.Mvc;
    
    namespace WebApplication4.Controllers
    {
        public class HomeController : Controller
        {
            public ActionResult Index()
            {
                string name = "";
                //Session里面有值，就表示已经登录
                if (Session["User"]!= null)
                {
                    name = Session["User"].ToString();
                }
                //Session=null就跳转到登录页面
                else
                {
                    return RedirectToAction("Login", "Login");
                }
                return Content("欢迎【"+name+"】登录");
            }      
        }
    }

2.登录页面

using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Web;
    using System.Web.Mvc;
    using WebApplication4.Filters;
    
    namespace WebApplication4.Controllers
    {
        //登录页加上此特性，不需要做登录验证，要不加会陷入死循环，导致浏览器崩溃
        [SkipCheckLoginAttribute]
        public class LoginController : Controller
        {
            // GET: Login
            [HttpGet]
            public ActionResult Login()
            {
                return View();
            }
            [HttpPost]
            public ActionResult Login(FormCollection forms)
            {
                string name = forms["name"];
                string pwd = forms["pwd"];
    
                if(name=="Admin" && pwd == "Admin")
                {
                    Session["User"] = name;
                }
    
                return RedirectToAction("Index","Home");
            }
        }
    }

View页的登录

@{
        Layout = null;
    }
    
    <!DOCTYPE html>
    
    <html>
    <head>
        <meta name="viewport" content="width=device-width" />
        <title>Login</title>
    </head>
    <body>
        <div>
            @using (Html.BeginForm("Login", "Login", FormMethod.Post))
            {
                <input type="text" name="name" /><br />
                <input type="text" name="pwd" /><br />
                <input type="submit" value="登录" />
            }
        </div>
    </body>
    </html>

3.一个登录验证的过滤器CheckLoginAttribute

using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Web;
    
    namespace WebApplication4.Filters
    {
        using System.Web.Mvc;
        /// <summary>
        /// 统一登陆验证
        /// </summary>
        public class CheckLoginAttribute:ActionFilterAttribute
        {
            //重写ActionFilterAttribute中的OnActionExecuted方法，表示在执行Action之前执行此方法
            public override void OnActionExecuted(ActionExecutedContext filterContext)
            {
                //判断Action方法的Control是否跳过登录验证
                if (filterContext.ActionDescriptor.ControllerDescriptor.IsDefined(typeof(SkipCheckLoginAttribute), false))
                {
                    return;
                }
                //判断Action方法是否跳过登录验证
                if (filterContext.ActionDescriptor.IsDefined(typeof(SkipCheckLoginAttribute), false))
                {
                    return;
                }
                if (filterContext.HttpContext.Session["User"] == null)
                {
                    //跳转方法1：
                    filterContext.HttpContext.Response.Redirect("/Login/Login");
                    //跳转方法2：
                    ViewResult view = new ViewResult();
                    //指定要返回的完整视图名称
                    view.ViewName = "~/View/Login/Login.cshtml";
                }
            }
        }
    }

4.一个跳过登录验证的自定义属性类SkipCheckLoginAttribute

using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Web;
    
    namespace WebApplication4.Filters
    {
        //要继承所有属性的基类Attribute
        public class SkipCheckLoginAttribute:Attribute
        {
    
        }
    }

5.把SkipCheckLoginAttribute添加到全局过滤器中

using System.Web;
    using System.Web.Mvc;
    using WebApplication4.Filters;
    
    namespace WebApplication4
    {
        public class FilterConfig
        {
            public static void RegisterGlobalFilters(GlobalFilterCollection filters)
            {
                filters.Add(new HandleErrorAttribute());
                //添加自定义过滤器
                filters.Add(new CheckLoginAttribute());
            }
        }
    }