Log4Net配置使用简记

1，引用Log4Net.dll 。当前为2.0.8.0版，可添加Nuget包。我的办法是从下载的包中直接引用相应.net版本的dll以减小项目体积

2，在App.config中增加<section>节和<log4net>节。注意一个配置文件最多只能有一个configSections节，如果有必须是第一个节点

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
    <configSections>
    <section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler, log4net" />
  </configSections>
    <startup> 
        <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.5" />
    </startup>
  <log4net>
    <logger name="logerror">
      <level value="ERROR" />
      <appender-ref ref="ErrorAppender" />
    </logger>
    <logger name="loginfo">
      <level value="INFO" />
      <appender-ref ref="InfoAppender" />
    </logger>
    <appender name="ErrorAppender" type="log4net.Appender.RollingFileAppender">
      <param name="File" value="Log\LogError\" />
      <param name="AppendToFile" value="true" />
      <param name="MaxSizeRollBackups" value="100" />
      <param name="MaxFileSize" value="10240" />
      <param name="StaticLogFileName" value="false" />
      <param name="DatePattern" value="yyyyMMdd&quot;.txt&quot;" />
      <param name="RollingStyle" value="Date" />
      <layout type="log4net.Layout.PatternLayout">
        <param name="ConversionPattern" value="%n异常时间：%d %n异常级别：%-5p%n异常内容：%m%n" />
      </layout>
      <!--&lt; &gt; = <> %n = 回车-->
    </appender>
    <appender name="InfoAppender" type="log4net.Appender.RollingFileAppender">
      <param name="File" value="Log\LogInfo\" />
      <param name="AppendToFile" value="true" />
      <param name="MaxFileSize" value="10240" />
      <param name="MaxSizeRollBackups" value="100" />
      <param name="StaticLogFileName" value="false" />
      <param name="DatePattern" value="yyyyMMdd&quot;.txt&quot;" />
      <param name="RollingStyle" value="Date" />
      <layout type="log4net.Layout.PatternLayout">
        <param name="ConversionPattern" value="日志时间：%d %n日志级别：%-5p  %n日志内容：%m%n%n" />
      </layout>
    </appender>
  </log4net>
</configuration>

3，项目AssemblyInfo.cs文件中增加一行代码，指明从配置文件中读取配置

[assembly: log4net.Config.XmlConfigurator(ConfigFileExtension = "config", Watch = true)]

4，项目中添加日志类

 public class LogHelper
    {
        private LogHelper()
        {
        }

        public static readonly log4net.ILog loginfo = log4net.LogManager.GetLogger("loginfo");

        public static readonly log4net.ILog logerror = log4net.LogManager.GetLogger("logerror");

        public static void SetConfig()
        {
            log4net.Config.XmlConfigurator.Configure();
        }

        public static void SetConfig(FileInfo configFile)
        {
            log4net.Config.XmlConfigurator.Configure(configFile);
        }

        public static void WriteLog(string info)
        {
            if (loginfo.IsInfoEnabled)
            {
                loginfo.Info(info);
            }
        }

        public static void WriteLog(string info, Exception se)
        {
            if (logerror.IsErrorEnabled)
            {
                logerror.Error(info, se);
            }
        }
    }

5，测试

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

namespace TestLog4Net
{
    class Program
    {
        static void Main(string[] args)
        {
            try
            {
                LogHelper.WriteLog("程序启动，正常记录！");
                int a = Convert.ToInt32("zzz");
            }
            catch (Exception ex)
            {
                LogHelper.WriteLog("错误", ex);
            }
        }
    }
}

6，测试结果：运行目录下生成log文件夹，其下两个文件夹：LogError，LogInfo，其内是以日期为文件名的Txt日志

参考：

　　C# 使用/配置Log4Net