log4net用法

1  NuGet 导入 log4net包

2 配置文件

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<!--log4net使用的类-->
  <configSections>
    <section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler, log4net"/>
  </configSections>

  <log4net>

    <root>
      <!-- 默认日志对象级别 -->
      <!--(高) OFF > FATAL > ERROR > WARN > INFO > DEBUG > ALL (低) -->
      <level value="ALL" />
　　
        <appender-ref ref="errorAppender" />
        <appender-ref ref="infoAppender" />
        <appender-ref ref="debugAppender" />
    </root>

<appender name="errorAppender" type="log4net.Appender.RollingFileAppender"> <filter type="log4net.Filter.LevelMatchFilter"> <levelToMatch value="ERROR" /> </filter> <filter type="log4net.Filter.DenyAllFilter" /> <file value="Logs\err.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 %logger - %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 %logger - %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 %logger - %message%newline" /> </layout> </appender> <appender name="perfAppender" type="log4net.Appender.RollingFileAppender"> <filter type="log4net.Filter.LevelMatchFilter"> <levelToMatch value="INFO" /> </filter> <filter type="log4net.Filter.DenyAllFilter" /> <file value="Logs\perf.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 %logger - %message%newline" /> </layout> </appender> <logger name="Performance" additivity="false"> <level value="ALL" /> <appender-ref ref="perfAppender" /> </logger> </log4net> </configuration>

root 中level级别 OFF > FATAL > ERROR > WARN > INFO > DEBUG > ALL       设置为warn  表示OFF > FATAL > ERROR > WARN  日志都写入，