一、程序集加载
[assembly: log4net.Config.XmlConfigurator(ConfigFile = @"Config\log4net.config", Watch = true)]
二、配置文件
<?xml version="1.0" encoding="utf-8" ?>
<log4net>
???<appender name="errorAppender" type="log4net.Appender.RollingFileAppender">
???????<filter type="log4net.Filter.LevelMatchFilter">
???????????<levelToMatch value="ERROR" />
???????</filter>
???????<filter type="log4net.Filter.DenyAllFilter" />
???????<file value="Logs\error.log" />
???????<encoding value="utf-8"/>
???????<preserveLogFileNameExtension value="true" />
???????<appendToFile value="true" />
???????<rollingStyle value="Date" />
???????<datePattern value="yyyyMMdd" />
???????<layout type="log4net.Layout.PatternLayout">
???????????<conversionPattern value="%date [%thread] %-5level - %message%newline" />
???????</layout>
???</appender>
???<appender name="infoAppender" type="log4net.Appender.RollingFileAppender">
???????<filter type="log4net.Filter.LevelMatchFilter">
???????????<levelToMatch value="INFO" />
???????</filter>
???????<filter type="log4net.Filter.DenyAllFilter" />
???????<file value="Logs\info.log" />
???????<encoding value="utf-8"/>
???????<preserveLogFileNameExtension value="true" />
???????<appendToFile value="true" />
???????<rollingStyle value="Date" />
???????<datePattern value="yyyyMMdd" />
???????<layout type="log4net.Layout.PatternLayout">
???????????<conversionPattern value="%date [%thread] %-5level - %message%newline" />
???????</layout>
???</appender>
???<appender name="debugAppender" type="log4net.Appender.RollingFileAppender">
???????<filter type="log4net.Filter.LevelMatchFilter">
???????????<levelToMatch value="DEBUG" />
???????</filter>
???????<filter type="log4net.Filter.DenyAllFilter" />
???????<file value="Logs\debug.log" />
???????<encoding value="utf-8"/>
???????<preserveLogFileNameExtension value="true" />
???????<appendToFile value="true" />
???????<rollingStyle value="Date" />
???????<datePattern value="yyyyMMdd" />
???????<layout type="log4net.Layout.PatternLayout">
???????????<conversionPattern value="%date [%thread] %-5level - %message%newline" />
???????</layout>
???</appender> ??
???<root>
???????<level value="ALL" />
???????<appender-ref ref="errorAppender" />
???????<appender-ref ref="infoAppender" />
???????<appender-ref ref="debugAppender" />
???</root> ???
</log4net>
log4net配置笔记
原文地址：https://www.cnblogs.com/ljsoftware/p/9050295.html