作用

实现

IAsyncResourceFilter

IAsyncResourceFilter

全局注册

builder.Services.AddControllersWithViews(
    options =>
    {
        //这样注册将对所有action 都生效
        options.Filters.Add<CustomAsyncResourceFilterAttribute>();
    }).AddControllersAsServices();

如何取body参数

Aop缓存简单示例

过滤器代码

using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Mvc.Filters;

namespace Cnpc.Com.Ioc.WebApp.Filter
{
    public class CustomAsyncResourceFilterAttribute : Attribute, IAsyncResourceFilter
    {
        private static Dictionary<string, IActionResult?> cache = new Dictionary<string, IActionResult?>();
        public async Task OnResourceExecutionAsync(ResourceExecutingContext context, ResourceExecutionDelegate next)
        {
            {
                Console.WriteLine("方法前 Async");
                string user_id = context.HttpContext.Request.Query["User"];
                if (cache.ContainsKey(user_id))
                {
                    context.Result = cache[user_id];
                }
                else
                {
                    ResourceExecutedContext exected = await next();
                    {
                        Console.WriteLine("方法后 Async");
                        cache[user_id] = exected.Result;
                    }
                }
            }

        }
    }
}

Action代码

using Cnpc.Com.Ioc.WebApp.Filter;
using Microsoft.AspNetCore.Mvc;

namespace Cnpc.Com.Ioc.WebApp.Controllers
{
    [Route("api/[controller]/[action]")]
    [ApiController]
    public class TestFilterController : ControllerBase
    {
        [CustomAsyncResourceFilter]
        [HttpPost]
        public async Task<ActionResult<User?>> LoginIn(string user, string pwd)
        {
            Console.WriteLine("LoginIn");
            await Task.CompletedTask;
            Thread.Sleep(3000);  //测试缓存是否生效,第一次会等3秒, 下一次找到User Action将不会执行
            return new User() { Login = user, Password = pwd };
        }
    }
}