log4net使用删除日志文件，保留指定数量的文件

1、打开visual studio 新建控制台项目  Consolelog4net

 2、选择项目  Consolelog4net，右键，选择 管理NuGet程序包，搜索log4net，点击安装，

3、新建类App.config文件，内容如下

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <configSections>
    <section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler, log4net" />
  </configSections>
  <log4net>
    <appender name="RollingLogFileAppender" type="log4net.Appender.RollingFileAppender">
      <file value="Log\Log.txt" />
      <appendToFile value="true" />
      <rollingStyle value="Size" />
      <maxSizeRollBackups value="4" />
      <maximumFileSize value="10KB" />
      <staticLogFileName value="true" />
      <layout type="log4net.Layout.PatternLayout">
        <!--<param name="ConversionPattern" value="%-5p %d [%c] [%l] %m%n" />-->
        <conversionPattern value="%-5level %date [%thread] - %message %newline" />
      </layout>
    </appender>
    <root>
      <level value="all" />
      <appender-ref ref="RollingLogFileAppender" />
    </root>
  </log4net>
</configuration>

4、新建类LoggerService.cs文件，内容如下

using log4net;
using System.Reflection;

namespace Consolelog4net
{
    /// <summary>
    /// 日志服务
    /// </summary>
    public class LoggerService
    {
        #region Fields and Properties
        public static ILog Log { get; } = LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType);
        static LoggerService()
        {
            log4net.Config.XmlConfigurator.Configure();
        }
        #endregion
    }
}

5、Program内容如下

using System;
using System.Threading;

namespace Consolelog4net
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("测试log4net的指定日志文件");
            while (true)
            {
                LoggerService.Log.Fatal("Fatal 123");
                LoggerService.Log.Error("Error 123");
                LoggerService.Log.Warn("Warn 123");
                LoggerService.Log.Info("Info 123");
                LoggerService.Log.Debug("Debug 123");

                //Thread.Sleep(TimeSpan.FromSeconds(1));
            }
        }
    }
}

6、测试