<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <!-- This section contains the log4net configuration settings -->
  <log4net>
    <!-- OFF, FATAL, ERROR, WARN, INFO, DEBUG, ALL -->
    <!-- Set root logger level to ERROR and its appenders -->
    <root>
      <level value="ALL"/>
      <appender-ref ref="SysAppender"/>
    </root>
    <!-- Print only messages of level DEBUG or above in the packages -->
    <logger name="WebLogger">
      <level value="DEBUG"/>
    </logger>
    
    <appender name="SysAppender" type="log4net.Appender.RollingFileAppender,log4net" >
      <param name="File" value="Content/Logs/" />
      <param name="AppendToFile" value="true" />
      <param name="RollingStyle" value="Date" />
      <param name="DatePattern" value="&quot;Logs_&quot;yyyyMMdd&quot;.txt&quot;" />
      <param name="StaticLogFileName" value="false" />
      <layout type="log4net.Layout.PatternLayout,log4net">
      <param name="ConversionPattern" value="%n日志时间：%d [%t] %n日志级别：%-5p %n日 志 类：%c [%L] %n%m %n" />
        <param name="Header" value="&#13;&#10;----------------------Header--------------------------&#13;&#10;" />
        <param name="Footer" value="&#13;&#10;----------------------Footer--------------------------&#13;&#10;" />
      </layout>
    </appender>
    
      
    <appender name="consoleApp" type="log4net.Appender.ConsoleAppender,log4net">
      <layout type="log4net.Layout.PatternLayout,log4net">
        <param name="ConversionPattern" value="%d [%t] %-5p %c - %m%n" />
      </layout>
    </appender>
  </log4net>

</configuration>

        ...

　　　　 public  static log4net.Repository.ILoggerRepository LogRepository { get; set; }
        public Startup(IConfiguration configuration)
        {
            Configuration = configuration;
            LogRepository = log4net.LogManager.CreateRepository("NetCoreRepository");
            log4net.Config.XmlConfigurator.Configure(LogRepository, new FileInfo(@"Config\log4net.config"));
        }
　　　　...

using log4net;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;

namespace CMSCore.Web.Core
{
    public class Log4Net
    {
        private static ILog log;
        static Log4Net()
        {
            log = LogManager.GetLogger(Startup.LogRepository.Name,typeof(Log4Net));
        }
        public static void Info(string message)
        {
            log.Info(message);
        }

        public static void Warn(string message)
        {
            log.Warn(message);
        }
        public static void Warn(string message,Exception ex)
        {
            log.Warn(message,ex);
        }

        public static void Error(string message)
        {
            log.Error(message);
        }
        public static void Error(string message,Exception ex)
        {
            log.Error(message,ex);
        }

        public static void Debug(string message)
        {
            log.Debug(message);
        }
        public static void Debug(string message, Exception ex)
        {
            log.Debug(message, ex);
        }

    }
}