Question

I am using Log4Net to log exceptions in my web application.

Here I have found an example for a configuration: http://www.csharptocsharp.com/log4net-configuration-for-rockin-loggin

<?xml version="1.0"?>

<configuration>
  <configSections>
        <section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler,log4net"/>
  </configSections>

  <log4net>
    <!--
  This writes the log information to the console window.  It only logs events
  that are at least at the INFO level (which would mean that DEBUG events are not
  captured.
  -->
    <appender name="ConsoleAppender" type="log4net.Appender.ConsoleAppender">
      <layout type="log4net.Layout.PatternLayout">
        <conversionPattern value="%date{ABSOLUTE} [%thread] %level %logger - %message%newlineExtra Info: %property{testProperty}%newline%exception"/>
      </layout>
      <filter type="log4net.Filter.LevelRangeFilter">
        <levelMin value="INFO"/>
        <levelMax value="FATAL"/>
      </filter>
    </appender>
    <!--
  This stores information in the log.txt file.  It only captures log events
  that contain the key word test or error.
  -->
    <appender name="RollingFileAppender" type="log4net.Appender.RollingFileAppender">
           <file value="L:\Name\trunk\Name.Web\log.txt"/>
      <appendToFile value="true"/>
      <rollingStyle value="Size"/>
      <maxSizeRollBackups value="5"/>
      <maximumFileSize value="10MB"/>
      <staticLogFileName value="true"/>
      <filter type="log4net.Filter.StringMatchFilter">
        <stringToMatch value="test"/>
      </filter>
      <filter type="log4net.Filter.StringMatchFilter">
        <stringToMatch value="error"/>
      </filter>
      <filter type="log4net.Filter.DenyAllFilter"/>
      <layout type="log4net.Layout.PatternLayout">
        <conversionPattern value="%date [%thread] %level %logger - %message%newline%exception"/>
      </layout>
    </appender>
    <root>
      <level value="FATAL"/>
      <appender-ref ref="RollingFileAppender"/>
    </root>
    <logger name="Log4NetTest.OtherClass">
      <level value="DEBUG"/>
      <appender-ref ref="ConsoleAppender"/>
    </logger>
  </log4net>


</configuration>

In my class I have:

protected static readonly ILog log = LogManager.GetLogger(typeof(TemplateController));

and in my method I have:

log4net.Config.XmlConfigurator.Configure();

                //————————–
                log.Error("sadi the great");
                log.Info("sadi the great");

but I have got error:

Answer 1

A working configuration for Rolling File appender is like this:

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
    <configSections>
        <section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler, log4net" />
    </configSections>
    <log4net>
         <appender name="RollingFile" type="log4net.Appender.RollingFileAppender">
             <file value="logger.log" />
             <appendToFile value="true" />
             <maximumFileSize value="100KB" />
             <maxSizeRollBackups value="2" />
             <layout type="log4net.Layout.PatternLayout">
             <conversionPattern value="%date %logger [%thread] [%ndc] (%file:%line) %level- %message%newline"/>
             </layout>
         </appender>

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

and you should change your target framework to “.net framework 4” (by default it is different in my case)
check this one will be useful