.NET Core MVC 登陸或權限過濾器

using AuthorizationCenter.Define;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Mvc.Controllers;
using Microsoft.AspNetCore.Mvc.Filters;
using System.Linq;

namespace AuthorizationCenter.Filters
{
    /// <summary>
    /// 登陸過濾器
    /// </summary>
    public class SignFilter : ActionFilterAttribute
    {
        /// <summary>
        /// 當動作執行中 
        /// </summary>
        /// <param name="context"></param>
        public override void OnActionExecuting(ActionExecutingContext context)
        {
            // 判斷是否檢查登陸
            var noNeedCheck = false;
            if (context.ActionDescriptor is ControllerActionDescriptor controllerActionDescriptor)
            {
                noNeedCheck = controllerActionDescriptor.MethodInfo.GetCustomAttributes(inherit: true)
                  .Any(a => a.GetType().Equals(typeof(NoSignAttribute)));
            }
            if (noNeedCheck) return;

            // 檢查登陸 - 在SignIn中判斷用戶合法性，將登陸信息保存在Session中，在SignOut中移除登陸信息
            // 獲取登陸信息 - 這里采用Session來保存登陸信息 -- Constants是字符串常量池
            var userid = context.HttpContext.Session.GetString(Constants.USERID);
            var signname = context.HttpContext.Session.GetString(Constants.SIGNNAME);
            var password = context.HttpContext.Session.GetString(Constants.PASSWORD);

            // 檢查登陸信息
            if (userid == null && signname == null)
            {
                // 用戶未登陸 - 跳轉到登陸界面
                context.Result = new RedirectResult("/Sign/Index");
            }
            base.OnActionExecuting(context);
        }
    }
    /// <summary>
    /// 不需要登陸的地方加個特性
    /// </summary>
    public class NoSignAttribute : ActionFilterAttribute { }
}

不需要登陸的地方加個特性

[NoSign]
public IActionResult SignIn()
{
    // TODO
}

需要注冊過濾器

public void ConfigureServices(IServiceCollection services)
{
    services.AddMvc(config =>config.Filters.Add(typeof(SignFilter))).SetCompatibilityVersion(CompatibilityVersion.Version_2_1);
    // Do Others
}

參考：
.net core 登入全局驗證過濾器
Asp.net Core過濾器