你在log4net配置中有什么？

<log4net>
  <appender name="RollingFileAppender" type="log4net.Appender.RollingFileAppender">
    <file value="logs/app.log" />
   <appendToFile value="true" />
   <rollingStyle value="Size" />
    <maxSizeRollBackups value="10" />
   <maximumFileSize value="10MB" />
   <staticLogFileName value="true" />
   <layout type="log4net.Layout.PatternLayout">
      <conversionPattern value="%date [%thread] %-5level %logger - %message%newline" />
    </layout>
  </appender>

  <root>
   <level value="DEBUG" />
    <appender-ref ref="RollingFileAppender" />
  </root>
</log4net>