log4net is not generating log.txt file

Question

I built a basic windows service in c# in VS2017 straight from the project template Windows Service. Built no problem. Installed no problem.

Here is the app.config with log4net section:

    <?xml version="1.0" encoding="utf-8" ?>
    <configuration>
        <startup> 
            <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.6.2" />
        </startup>
        <log4net>
            <appender name="FileAppender" type="log4net.Appender.FileAppender">
                <file value="log.txt" />
                <appendToFile value="true" />
                <layout type="log4net.Layout.PatternLayout">
                    <conversionPattern value="%date [%thread] %-5level %logger - %message%newline" />
                </layout>
            </appender>
            <appender name="ConsoleAppender" type="log4net.Appender.ColoredConsoleAppender">
                <mapping>
                    <level value="ERROR" />
                    <backColor value="Red, HighIntensity" />
                </mapping>
                <mapping>
                    <level value="WARN" />
                    <foreColor value="White" />
                    <backColor value="Yellow" />
                </mapping>
                <mapping>
                    <level value="INFO" />
                    <foreColor value="White" />
                </mapping>
                <mapping>
                    <level value="DEBUG" />
                    <backColor value="Green" />
                </mapping>
                <layout type="log4net.Layout.PatternLayout">
                    <conversionPattern value="%date [%thread] %-5level %logger - %message%newline" />
                </layout>
            </appender>
            <root>
                <level value="ALL" />
                <appender-ref ref="ConsoleAppender" />
                <appender-ref ref="FileAppender" />
            </root>
        </log4net>
    </configuration>

And I want to log some events, like here:

public partial class Service1 : ServiceBase
{
    private ILog log = LogManager.GetLogger(typeof(Service1));

    public Service1()
    {
        InitializeComponent();
        XmlConfigurator.Configure();
    }

    protected override void OnStart(string[] args)
    {
        log.Info("OnStart");
    }

    protected override void OnStop()
    {
        log.Info("OnStop");
    }
}

When I start the service, I dont see any log.txt file created in the folder where the exe resides (Debug\Bin).

Any idea why?

Question: why did you choose log4net? I was looking at it today after reading an article — Daniel Loudon, Sep 07 '18 at 17:34
its very powerful and in my company we are using log4net everywhere — monstro, Sep 07 '18 at 17:41
I was looking for a way to audit a sql database and was looking at log4net, serilog and netlog — Daniel Loudon, Sep 07 '18 at 17:42
log4net can output message to practically anywhere, text file, database, console, etc... — monstro, Sep 07 '18 at 17:42
@monstro See this. I think you need to specify the directory explicitly. https://stackoverflow.com/questions/884963/what-directory-does-a-windows-service-run-in — Matt M, Sep 07 '18 at 17:43

score 1 · Answer 1 · answered Sep 07 '18 at 17:57

I think the issue here I think is that your log variable is being initialized prior to the constructor being called. So basically you are calling LogManager.GetLogger prior to calling XmlConfigurator.Configure()

Try initializing log in the constructor after configuring log4net and see if that solves your problem.

public Service1()
{
    InitializeComponent();
    XmlConfigurator.Configure();
    log = LogManager.GetLogger(typeof(Service1));
}

score 1 · Answer 2 · answered Sep 07 '18 at 19:05

1

Adding another answer since my previous hunch seemed to be wrong (or maybe you actually have two problems here). Assuming you posted your whole app.config file, it doesn't look like you declare the log4net config section anywhere in there:

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

Perhaps that's the problem?

answered Sep 07 '18 at 19:05

Eric Petroelje

59,820
9
127
177

I have this defined – monstro Sep 10 '18 at 11:31

score 0 · Answer 3 · answered Sep 07 '18 at 18:00

In my particular case, we always set the app.config file when initialize Log4Net on the Class Constructor:

 log4net.Config.XmlConfigurator.Configure(new Uri(Path.Combine(Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location), "YouAppConfigFile.config")));
 Log = log4net.LogManager.GetLogger("ServiceClass1");
 Log.Info("ServiceClass1 Started!!!");

log4net is not generating log.txt file

3 Answers3