.NET CORE 3.1 MVC Log4net

 public void Configure(IApplicationBuilder app, IWebHostEnvironment env, ILoggerFactory loggerFactory)
        {
            loggerFactory.AddLog4Net();
            if (env.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
            }
            else
            {
                app.UseExceptionHandler("/Home/Error");
                // The default HSTS value is 30 days. You may want to change this for production scenarios, see https://aka.ms/aspnetcore-hsts.
                app.UseHsts();
            }
            app.UseHttpsRedirection();
            app.UseStaticFiles();
            app.UseRouting();
            app.UseAuthorization();
            app.UseEndpoints(endpoints =>
            {
                endpoints.MapControllerRoute(
                    name: "default",
                    pattern: "{controller=Home}/{action=Index}/{id?}");
            });
        }
 
3 配置log4net.config
<log4net>
 <root>
		<level value="ALL" ref="infoAppender" />
		<appender-ref ref="infoAppender" />
		<appender-ref ref="errorAppender" />
		<appender-ref ref="debugAppender" />
	</root>
	<!-- 日志的等级，它们由高到底分别为： OFF > FATAL > ERROR > WARN > INFO > DEBUG > ALL -->
	<!--信息日志配置-->
	<!--<appender name="infoAppender" type="log4net.Appender.RollingFileAppender">
		<param name="File" value="../../../Logs/Info/info.log" />
		<param name="AppendToFile" value="false" />
		<param name="MaxFileSize" value="10240" />
		<param name="MaxSizeRollBackups" value="100" />
		<param name="PreserveLogFileNameExtension" value="true" />
		<param name="StaticLogFileName" value="false" />
		<param name="DatePattern" value="yyyyMMdd" />
		<param name="RollingStyle" value="Date" />
		<layout type="log4net.Layout.PatternLayout">
			<conversionPattern value="%date [%thread] %-5level %logger - %message%newline" />
		</layout>
		<filter type="log4net.Filter.LevelRangeFilter">
			<param name="LevelMin" value="OFF" />
			<param name="LevelMax" value="OFF" />
		</filter>
	</appender>-->
	<!--调试日志配置-->
	<!--<appender name="debugAppender" type="log4net.Appender.RollingFileAppender">
		<param name="File" value="../../../Logs/Debug/debug.log" />
		<param name="AppendToFile" value="false" />
		<param name="MaxFileSize" value="10240" />
		<param name="MaxSizeRollBackups" value="100" />
		<param name="PreserveLogFileNameExtension" value="true" />
		<param name="StaticLogFileName" value="false" />
		<param name="DatePattern" value="yyyyMMdd" />
		<param name="RollingStyle" value="Date" />
		<layout type="log4net.Layout.PatternLayout">
			<conversionPattern value="%date [%thread] %-5level %logger - %message%newline" />
		</layout>
		<filter type="log4net.Filter.LevelRangeFilter">
			<param name="LevelMin" value="OFF" />
			<param name="LevelMax" value="OFF" />
		</filter>
	</appender>-->
	<!--错误日志配置-->
	<appender name="errorAppender" type="log4net.Appender.RollingFileAppender">
		<param name="File" value="../../../Logs/Error/Err.log" />
		<param name="AppendToFile" value="true" />
		<param name="MaxFileSize" value="10240" />
Backups" value="100" />
		<param name="PreserveLogFileNameExtension" value="true" />
		<param name="StaticLogFileName" value="false" />
		<param name="DatePattern" value="yyyyMMdd" />
		<param name="RollingStyle" value="Date" />
		<layout type="log4net.Layout.PatternLayout">
			<conversionPattern value="%date [%thread] %-5level %logger - %message%newline" />
		</layout>
		<filter type="log4net.Filter.LevelRangeFilter">
			<param name="LevelMin" value="ERROR" />
			<param name="LevelMax" value="ERROR" />
		</filter>
	</appender>
</log4net>
 
4  项目实际使用
 public class HomeController : Controller
    {
        private readonly ILogger<HomeController> _logger;
        public HomeController(ILogger<HomeController> logger)
        {
            _logger = logger;
        }
 
        public IActionResult Privacy()
        {
            _logger.LogError("这里记录的是LogError: 您在" + DateTime.Now.ToString()+"查看了Privacy" );
        
            return View();
        }

    }
5 效果展示