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Log4net not working in multithreading in C#

hello friends i have added log4net package form nuget packages. for sync call log4net add logs in log file but when i am declaring a methods using Task its not working
<log4net>
<appender name="TestAppender" type="log4net.Appender.RollingFileAppender">
<file value="D:\log\logswebapi.log" />
<encoding value="utf-8" />
<appendToFile value="true" />
<rollingStyle value="Date" />
<layout type="log4net.Layout.PatternLayout">
<!--<conversionPattern value="%date %level [%thread] %type.%method - %message%n" />-->
</layout>
</appender>
<root>
<level value="All" />
<!-- If the following line is not included the log file
will not be created even if log4net is configured with this file. -->
<appender-ref ref="TestAppender" />
</root>
</log4net>
i have added this code in web.config file
private void AddLog(string str)
{
ILog Log = LogManager.GetLogger(System.Reflection.MethodBase.GetCurrentMethod().DeclaringType);
Log.Info(DateTime.Now + " - " + str);
}
public string SendDocument(){
// send document logic
AddLog(send document done");
}
public string Response(){
Task.Run(() =>SendDocument()); // here i am calling this senddocument method in thread
}
in above code Response method i am calling send document methods in thread but logs are not added now how to resolve this issue ?
thanks in advance

Configuring log4net without code in Rider for dotnet 2.1 project

I'm working on a pet .netcore2.1 project using Rider IDE. I'm currently trying to add log4net support for the project, and trying to do it the "proper way" (separate config file, automatically configure log4net without having to write code for intialization etc.). So far all tutorials (ex1, ex2) I've found suggest configuring it by adding assembly property
[assembly: log4net.Config.XmlConfigurator(Watch=true)]
to AssemblyInfo.cs file. However I seem to fail to find the file, and it looks from other questions (e.g. this) that it might not be used with .netcore at all, in favor of doing configuration via other means (e.g. .csproj file).
So far I've found a workaround here, which works, but it uses explicit configuration via code, which looks like a step backwards compared to assembly-level configuration.
Is there a way of doing this in a more static way (e.g. using some ItemGroup in .csproj)?
Upd: for future reference - this is just a custom case of https://learn.microsoft.com/en-us/dotnet/standard/assembly/set-attributes , so it just goes to .cs file directly.

Easy example using log4net for .net core in console:
[assembly: XmlConfigurator(Watch = true)]
namespace ConsoleApp
{
class Program
{
private static readonly ILog log = LogManager.GetLogger(typeof(Program));
static void Main(string[] args)
{
var logRepository = LogManager.GetRepository(Assembly.GetEntryAssembly());
XmlConfigurator.Configure(logRepository, new FileInfo("log4net.config"));
log.Info("Entering application.");
log.Error("Error application.");
}
}
}
You need to add file with settings log4net to your project: log4net.config, and don't forget chnage it options "Copy to output directory" to "Copy if newer" or "Copy always"
Example of log4net.config:
<?xml version="1.0" encoding="utf-8" ?>
<log4net>
<appender name="ConsoleAppender" type="log4net.Appender.ConsoleAppender" >
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date [%thread] %-5level %logger [%ndc] - %message%newline" />
</layout>
</appender>
<appender name="FileAppender" type="log4net.Appender.RollingFileAppender">
<lockingModel type="log4net.Appender.FileAppender+MinimalLock" />
<file value="logs/" />
<datePattern value="yyyy-MM-dd'.log'" />
<staticLogFileName value="false" />
<appendToFile value="true" />
<rollingStyle value="Composite" />
<layout type="log4net.Layout.PatternLayout">
<IgnoresException value="False" />
<conversionPattern value="%date [%thread] %-5level %logger [%ndc] - %message%newline" />
</layout>
<filter type="log4net.Filter.LevelRangeFilter">
<param name="LevelMin" value="INFO"/>
</filter>
</appender>
<root>
<level value="ALL" />
<appender-ref ref="FileAppender" />
<appender-ref ref="ConsoleAppender" />
</root>
</log4net>
By the way: log4net don't supporting for 1 april 2020: http://logging.apache.org/log4net/

Log4net not logging on Azure Webapp

For a web service, I have log4net configured and working fine locally but not when the webapp is deployed on Azure Webapp. The directory is created but there is nothing logged at the file..
Here is my config:
<log4net>
<appender name="RollingFile" type="log4net.Appender.RollingFileAppender">
<file value="log/sms.log" />
<appendToFile value="true" />
<maximumFileSize value="10MB" />
<maxSizeRollBackups value="10" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date %level - %message%newline" />
</layout>
</appender>
<logger name="TheLogger">
<appender-ref ref="RollingFile" />
</logger>
Within my AssemblyInfo.cs I have:
[assembly: XmlConfigurator(Watch = true)]
At the Startup class i have :
public static ILog Logger { get; private set; }
public void Configuration(IAppBuilder appBuilder)
{
Logger = LogManager.GetLogger("TheLogger");
Logger.Info("Application start...");
}
Clearly my configuration is being picked up because in my log file is written the hour/date format and also Application start... but not the logging information.
What am i missing?

Make sure you don't forget to add the root configuration.
Are compiling for Debug and deploying in Azure in Release mode?
<log4net>
<root>
<level value="INFO" />
<appender-ref ref="RollingFile" />
</root>
<appender name="RollingFile" type="log4net.Appender.RollingFileAppender">
<!-- ... -->
</appender>
</log4net>

I had the same problem and found a solution. I had to replace these 2 lines of code in the Program class of the .Net Core API:
XmlDocument log4netConfig = new XmlDocument();
log4netConfig.Load(File.OpenRead("log4net.config"));
With this:
var logRepository = LogManager.GetRepository(Assembly.GetEntryAssembly());
XmlConfigurator.Configure(logRepository, new FileInfo("log4net.config"));
The reason is because in .Net Framework API's I used the assembly attribute to set this, now I need to do it like this.

Configure Log4Net for the full project

I have the following code which Logs everything very nicely. Am I going to have to add this to the constructor of all of my classes?
Is there anyway to configure it for the full project? I suppose I could pass log around to all of the classes but that seams like a messy solution.
class Program
{
/// <summary>
/// Application start
/// <param name="settings"></param>
/// <returns></returns>
static int Main(string[] args)
{
string logFile = string.Format(#"{0}\Cloud\Cloud.Log", Environment.GetFolderPath(Environment.SpecialFolder.CommonApplicationData));
log4net.GlobalContext.Properties["LogFileName"] = logFile;
log4net.Config.XmlConfigurator.Configure();
ILog log = log4net.LogManager.GetLogger(typeof(Program));
log.Info("Console Applicatin Start");
}
}
How should can I configure Log4Net for the full solution?
I didn't think it was relevant to the question but here is my my App.config:
<configSections>
<section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler, log4net" />
</configSections>
<log4net>
<appender name="RollingFileAppender" type="log4net.Appender.RollingFileAppender">
<file type="log4net.Util.PatternString" value="%property{LogFileName}.txt" />
<appendToFile value="true" />
<rollingStyle value="Size" />
<maxSizeRollBackups value="10" />
<maximumFileSize value="250KB" />
<staticLogFileName value="true" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date [%thread] %-5level %logger [%property{NDC}] - %message%newline" />
</layout>
</appender>
<root>
<level value="ALL" />
<appender-ref ref="RollingFileAppender" />
</root>
</log4net>

I usually use a wrapper class. Something like:
public class Logger
{
private static readonly log4net.ILog _log = log4net.LogManager.GetLogger(typeof(Logger));
static Logger()
{
log4net.Config.XmlConfigurator.Configure();
}
public void Error(string format, params object[] args)
{
_log.Error(string.Format(format, args));
}
//...
}
And then just instantiate that where I need it. Like:
private Logger _log = new Logger();
And the use it like:
_log.Error("Something went wrong, Exception: {0}, More parameters: {1}",
e.Message, "Another parameter");
The
log4net.Config.XmlConfigurator.Configure();
Should configure log4net according to your app.config.
Edit:
I thought I'd post my log4net config, in case you want to try one that has been confirmed working. It sets up a file logger and a console logger (useful to see logging i development environment):
<log4net>
<root>
<level value="ALL" />
<appender-ref ref="ConsoleAppender" />
<appender-ref ref="DebugFileLogger" />
</root>
<appender name="ConsoleAppender" type="log4net.Appender.ConsoleAppender">
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date [%thread] %-5level %logger: %message%newline" />
</layout>
</appender>
<appender name="DebugFileLogger" type="log4net.Appender.RollingFileAppender">
<param name="File" value="Logs/DebugLog.log" />
<lockingModel type="log4net.Appender.FileAppender+MinimalLock" />
<appendToFile value="true" />
<rollingStyle value="Size" />
<maxSizeRollBackups value="10" />
<maximumFileSize value="20MB" />
<staticLogFileName value="true" />
<layout type="log4net.Layout.PatternLayout">
<param name="ConversionPattern" value="%d%t %m%n" />
</layout>
</appender>
</log4net>

One of the great features of log4net is the ability to configure filtering and processing differently depending on the logger name: any solution that wraps the logger in a wrapper, singleton or static object loses that as all logs will use the same logger name - and the useful ability to immediately see what class a log entry came from.
All you need in a class where you want to log is a field, eg:
private static ILog Log =
LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType);
which sets the logger name to the name of the type it's contained in.

The solution I see most often, is to create a LogManager class, and a property in each class to fetch an instance of a logger, so this is the only lines of code needed in each class to get a logger:
private ILog _log;
public ILog Log
{
get { return _log ?? (_log = LogManager.GetLogger(LogName.WebServices)); }
}
The LogName.WebServices is an Enum value, and should be extended with more values, so you are able to filter your logs even more.

log4net BasicConfigurator is not printing on console

I decided to use log4net to handle all the logging activities for the application I am working on... after reading through documentation, I decided to start making experiments, but failed miserably at the very first attempt
The application is being developed with c# using MonoDevelop 3.0.3.2 in a fairly standard Debian 7 distribution, in order to later be deployed on Linux machines.
The code is trivial so far and follows the very early steps in the log4net documentation, and is quoted at the end of the post.
The problem is that the logger does not print anything to console; while trying to understand what's going wrong, I looked intoo it with the debugger; I see that the log reference contains the AppendersCollection, which unfortunately is empty I guess that something is not working properly during configuration and I have no appenders, hence there is no log output.
What am I missing? any suggestion? Is there some sort of a known issue for the combination of MonoDevelop-Linux-log4net I am not aware of?
using System;
using log4net;
using log4net.Config;
namespace TestLog4Net
{
class MainClass
{
private static readonly ILog log = LogManager.GetLogger(typeof(MainClass));
public static void Main (string[] args)
{
BasicConfigurator.Configure();
Console.WriteLine ("Hello World!");
log.Info("Hello World!");
}
}
}
UPDATE
I did some tests loading the configuration file.
I created 3 loggers each with its own appender, two are rolling file appenders, and one is the console appender.
Then I log "Hello World!" on each logger.
The rolling file loggers work as expected, while the output from the ConsoleLogger is nowhere to be found. I checked with the Debugger and the clogger object does NOT display an empty AppenderCollection, but there no output anyway. Below you can find the updated code along with the configuration file.
using System;
using log4net;
using log4net.Config;
namespace TestLog4Net
{
class MainClass
{
public static void Main (string[] args)
{
XmlConfigurator.Configure(new System.IO.FileInfo("app.config"));
ILog rflogger1 = LogManager.GetLogger("RFLoggerOne");
ILog rflogger2 = LogManager.GetLogger("RFLoggerTwo");
ILog clogger = LogManager.GetLogger("CLogger");
rflogger1.Info("Hello World!");
rflogger2.Info("Hello World!");
clogger.Info("Hello World!");
Console.WriteLine ("Hello World!");
}
}
}
<log4net>
<appender name="CAppender" type="log4net.Appender.AnsiColorTerminalAppender">
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date [%thread] %-5level %logger [%property{NDC}] - %message%newline" />
</layout>
</appender>
<appender name="RFAppender1" type="log4net.Appender.RollingFileAppender">
<file value="rf1.log"/>
<appendToFile value="true"/>
<rollingStyle value="Composite"/>
<datePattern value="yyyyMMdd"/>
<maxSizeRollBackups value="10"/>
<maximumFileSize value="1000000"/>
<staticLogFileName value="true"/>
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date [%thread] %level %logger - %message%newline"/>
</layout>
</appender>
<appender name="RFAppender2" type="log4net.Appender.RollingFileAppender">
<file value="rf2.log" />
<appendToFile value="true" />
<maximumFileSize value="100KB" />
<maxSizeRollBackups value="2" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%level %thread %logger - %message%newline" />
</layout>
</appender>
<logger name="CLogger">
<level value="ALL"/>
<appender-ref ref="CAppender"/>
</logger>
<logger name="RFLoggerOne">
<level value="ALL"/>
<appender-ref ref="RFAppender1"/>
</logger>
<logger name="RFLoggerTwo">
<level value="ALL"/>
<appender-ref ref="RFAppender2"/>
</logger>
<root>
<level value="ALL"/>
</root>
</log4net>

Which kind of project do you use? A Console Application?
There are several cases you wont see any output on std::out or std::err on your console.
Have a look at this post:
Can one executable be both a console and GUI application?