1. 引入log4net、Microsoft.Extensions.Logging.Log4Net.AspNetCore包

2. 添加log4net配置文件

3. 在Program中添加如下代码：

public static IHostBuilder CreateHostBuilder(string[] args) => Host.CreateDefaultBuilder(args) .ConfigureLogging((context, logger) => { logger.ClearProviders(); logger.AddLog4Net(new Log4NetProviderOptions() { Log4NetConfigFileName = "Config/log4net.xml", Watch = true }); }) .ConfigureWebHostDefaults(webBuilder => { webBuilder.UseStartup<Startup>(); });

4. 在需要记录日志的类中通过构造函数引入：

public class ActionExceptionHandlerAttribute : Attribute, IActionFilter { private readonly ILogger<ActionExceptionHandlerAttribute> _logger; public ActionExceptionHandlerAttribute(ILogger<ActionExceptionHandlerAttribute> logger) { _logger = logger; } }

asp.net core 3.0在Microsoft.Extensions.Logging中添加log4net支持