log4net preserveLogFileNameExtension 和 watch

preserveLogFileNameExtension 

<log4net>
    <appender name="fileappender" type="log4net.Appender.RollingFileAppender">
      <file value="logprogram.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{yyyy-MM-dd HH:mm:ss.fffzzz} %-5p [%t]: %m%n" />
      </layout>
      <lockingModel type="log4net.Appender.FileAppender+MinimalLock"/>
    </appender>
    <appender name="wcfAppender" type="log4net.Appender.RollingFileAppender">
      <filter type="log4net.Filter.LevelMatchFilter">
        <levelToMatch value="Error" />
      </filter>
      <filter type="log4net.Filter.DenyAllFilter" />
      <file value="logCommunicationException.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{yyyy-MM-dd HH:mm:ss.fffzzz} %logger - %message%newline" />
      </layout>
      <lockingModel type="log4net.Appender.FileAppender+MinimalLock"/>
    </appender>
    <root>
      <level value="Info" />
      <appender-ref ref="fileappender" />
    </root>
    <logger name="WcfException" additivity="false">
      <level value="ALL" />
      <appender-ref ref="wcfAppender" />
    </logger>
  </log4net>

<preserveLogFileNameExtension value="true" />
这个属性的作用是，当前这一天的日志文件按照file来生成。在第二天的时候，把前一天的日志，加上datePattern。

 watch

https://logging.apache.org/log4net/release/manual/configuration.html

 在appsetting中加上

<appSettings>
  <add key="log4net.Config" value="log4net.config"/>
  <add key="log4net.Config.Watch" value="True"/>
</appSettings>