Log4net - Does not create a log file

Question

I'm using log4net in order to create a log, but it doesn't do anything.

Here is the app.config:

<?xml version="1.0" encoding="utf-8">
<configuration>
    <configSection>
        <section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler, log4net" />
    </configSection>
    <log4net>
        <appender name="WriteToFile" type="log4net.Appender.FileAppender">
            <file value="log.txt" />
            <layout ="log4net.Layout.SimpleLayout" />
        </appender>
        <root>
            <level value="ALL" />
            <appender-ref ref="WriteToFile"/>
        </root>
    </log4net>
</configuration>

I have the following line in AssemblyInfo.cs:

[assembly: log4net.Config.XmlConfigur(ConfigFile ="App.config", Watch= true)]

Here is an attempt to write to the file:

private static readonly ILog log = log4net.LogManager.GetLogger(System.Reflection.MethodBase.GetCurrentMethod().DeclaringType);

public void write()
{
    log.Info("Some text here");
}

And the following line:

log4net.Config.XmlConfigurator.Configure();

Try this, I think it help you. http://stackoverflow.com/questions/1321261/configuring-log4net-with-xml-file — Brian, Dec 13 '15 at 07:23
are you running your program in some folder where you don't have write permissions? — BeerBaron, Dec 15 '15 at 11:09

Darin Dimitrov · Accepted Answer · 2015-12-13T07:47:55.987

If this is an executable I suppose that your config file is not called App.config at the resulting bin folder but rather MyApp.exe.config. So you may try fixing this:

ConfigFile ="App.config"

You can also skip the config file name if you are using the default:

[assembly: log4net.Config.XmlConfigurator(Watch = true)]

Also make sure that the account you are running your application under has write permission to the folder in which you expect the log file to be written.

UPDATE:

Step by step guide:

Create a new Console Application
Install the log4net NuGet

Use the following in your App.config:

<?xml version="1.0" encoding="utf-8"?>
<configuration>
    <configSections>
        <section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler, log4net" />
    </configSections>
    <log4net>
        <appender name="WriteToFile" type="log4net.Appender.FileAppender">
            <file value="log.txt" />
            <layout type="log4net.Layout.SimpleLayout" />
        </appender>
        <root>
            <level value="ALL" />
            <appender-ref ref="WriteToFile" />
        </root>
    </log4net>
</configuration>

And in your Program.cs:

using log4net;
using System.Reflection;

[assembly: log4net.Config.XmlConfigurator(Watch = true)]

namespace ConsoleApplication1
{
    class Program
    {
        private static readonly ILog log = LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType);

        static void Main(string[] args)
        {
            log.Info("Some text here");
        }
    }
}

I have updated my answer with a step by step guide to a working example. I am not quite sure if it was a typo in your post or rather you have this in your actual code, but the XML configuration file you showed is invalid. For example the XML declaration is missing a closing `?`, also this is invalid: ``, ... — Darin Dimitrov, Dec 13 '15 at 07:48
Hmm, weird, those very same steps worked perfectly fine for me. Which version of `log4net` are you using? I used the latest one: 2.0.5 — Darin Dimitrov, Dec 13 '15 at 07:56
I tested for version 2.0.8 and it works. I run the app as admin. — zapoo, May 16 '17 at 14:45

score 2 · Answer 2 · answered Dec 13 '15 at 07:56

I have only been successful with log4net when I ran the static Configure method:

        log4net.Config.XmlConfigurator.Configure();

Wrapping it in one method below read default config for the application, be it web.config or app.config:

    private static void InitLogging()
    {
        log4net.Config.XmlConfigurator.Configure();
        _logger = Common.Logging.LogManager.GetLogger(typeof(Program));
        _logger.Debug("Logging initialized");
    }

It seems more elegant with an decorator attribute the way you are suggesting, but the above mentioned may be worth a try.

Log4net - Does not create a log file

2 Answers2