Why isn't ConsoleAppender configured in app.config causing logs to write to the console?

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In App.Config I declare a config section for my console application:

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

And configure a ConsoleAppender:

<log4net>
  <appender name="ConsoleAppender" type="log4net.Appender.ConsoleAppender">
    <layout type="log4net.Layout.PatternLayout">
    </layout>
  </appender>
  <root>
    <level value="ALL" />
    <appender-ref ref="ConsoleAppender" />
  </root>
</log4net>

We also declare a RollingFile appender in a logging util class that's part of our standard codebase at app-startup (which is not easily modified):

        _hierarchy = (Hierarchy)LogManager.GetRepository();
        _rollingFileAppender = new RollingFileAppender();            
        ... //_rollingFileppender options

        _rollingFileAppender.ActivateOptions();
        _hierarchy.Root.AddAppender(_rollingFileAppender);
        _hierarchy.Configured = true;

When I run the application, I see log-entries are written to files as expected but nothing is written to the console.

When I inspect my ILog instance in the debugger, I see no appenders at all in Logger.Appenders but I do see the RollingFileAppender instance as the only element in Root.Appenders.

log4net is something I am used to "it just works" - is there some incompatibility having config and code add appenders, or some line I need to get LogManager to look in app.config?

log4net .net c#
2 Answers

You just got me curious and i decided to play around a bit.
First observations is: You are right.

After some google i found this this

App.config

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <configSections>
    <section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler, log4net" />
  </configSections>
  <log4net>
    <appender name="ConsoleAppender" type="log4net.Appender.ColoredConsoleAppender">
      <layout type="log4net.Layout.PatternLayout">
        <conversionPattern value="%date %level [%thread] %logger{1} %username - %message%newline" />
      </layout>
      <mapping>
        <level value="WARN" />
        <foreColor value="Yellow, HighIntensity" />
      </mapping>
      <mapping>
        <level value="ERROR" />
        <foreColor value="Red, HighIntensity" />
      </mapping>
    </appender>
    <root>
      <level value="ALL" />
      <appender-ref ref="ConsoleAppender" />
    </root>
  </log4net>
  <startup> 
        <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.7.2" />
    </startup>
</configuration>

Setup

using log4net;
using log4net.Appender;
using log4net.Layout;
using log4net.Repository.Hierarchy;

namespace LoggerDemo
{
    public static class Program
    {
        private static readonly ILog Logger = LogManager.GetLogger(System.Reflection.MethodBase.GetCurrentMethod().DeclaringType);

        public static void Main(string[] args)
        {
            SetupFileAppender();
            SetupTraceAppender();
            Logger.Error("Error");
        }

        private static void SetupTraceAppender()
        {
            var patternLayout = new PatternLayout();
            patternLayout.ConversionPattern = "%date [%thread] %-5level %logger - %message%newline";
            patternLayout.ActivateOptions();

            var trace = new TraceAppender();
            trace.Layout = patternLayout;
            trace.ActivateOptions();
            var l = (Logger)Logger.Logger;
            l.AddAppender(trace);
        }

        private static void SetupFileAppender()
        {
            var patternLayout = new PatternLayout();
            patternLayout.ConversionPattern = "%date [%thread] %-5level %logger - %message%newline";
            patternLayout.ActivateOptions();

            var roller = new RollingFileAppender();
            roller.AppendToFile = true;
            roller.File = "Log.txt";
            roller.Layout = patternLayout;
            roller.MaxSizeRollBackups = 5;
            roller.RollingStyle = RollingFileAppender.RollingMode.Size;
            roller.StaticLogFileName = true;
            roller.ActivateOptions();
            var l = (Logger)Logger.Logger;
            l.AddAppender(roller);
        }
    }
}

Most Important

In your AssemblyInfo add [assembly: log4net.Config.XmlConfigurator(Watch = true)]

Result

Result

user_45580290

I looked in google about log4net and seems interesting. I looked into some website and for the output here should be something like log4net.config i guess? The guy showed to press it and in the Properties here should be "Copy to Output Directory": "Copy Always". Maybe you can somehow figure to use it and print into the console the output. Here is really useful information in google about it you can click Here to read more. Hope i somehow helped you :)

user_136808620
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