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Log4Net not working in MVC web application but working in console and window application

I have created a solution which consist of class library, MVC web application and console application.
For my class library project is actually responsible to perform logging using log4net which is also included the log4net configuration in the log4net.config. Currently i am facing a problem which the logging is not working when my web application call the logging function from class library. But it's working fine when my console application. My log4net.config looks as below:
<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<log4net>
<appender name="RollingLogFileAppender" type="log4net.Appender.RollingFileAppender">
<file value="C:\\Temp\" />
<datePattern value="'Test.log_'yyyy-MM-dd'.log'" />
<appendToFile value="true" />
<rollingStyle value="Date" />
<appendToFile value="true" />
<staticLogFileName value="false" />
<layout type="log4net.Layout.PatternLayout, log4net">
<conversionPattern value="%date [%thread] %-5level %logger [%method] - %message%newline" />
</layout>
</appender>
<root>
<level value="INFO" />
<appender-ref ref="RollingLogFileAppender" />
</root>
</log4net>
</configuration>
I have also included the line below in my class library [AssemblyInfo.cs]
[assembly: log4net.Config.XmlConfigurator(ConfigFile = "log4net.config", Watch = true)]
My sample class library function as below:
private static readonly log4net.ILog log =
log4net.LogManager.GetLogger(System.Reflection.MethodBase.GetCurrentMethod().DeclaringType);
public void Write ()
{
log.Info("Success");
}
I have set the log4net.config Copy to Output Directory to Copy always.
Sample log4net output from console application [Test.log_yyyy-MM-dd.log]:
2019-10-01 12:07:48,923 [1] INFO ClassLibrary2.Class1 [Write] - Success
But there is log file generated for MVC web application. Is there any additional step need to configure for the web application?
I would be grateful for any help with it.
Thanks.

Did you add something in your Application_Start method? (global.asax) like:
string l4net = Server.MapPath("~/log4net.config");
log4net.Config.XmlConfigurator.ConfigureAndWatch(new System.IO.FileInfo(l4net));

Try To Add ConfigSections in your web.config. Also there's the guide especially for MVC applications.
<configSections>
<section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler, log4net" />
</configSections>
Complete Guide

Cannot get Log4net to work from Class Library

I have a class library that performs a routine needed for installation. From everything I have researched, I believe I have things set up correctly. However, the routine absolutely will not log anything. Here is what I have:
I have added the class library project as a reference to the host project.
In my class library, I have the following:
private static readonly ILog Log = LogManager.GetLogger(System.Reflection.MethodBase.GetCurrentMethod().DeclaringType);
public InstallDLL() {
Log.Error("Where are you goinng?");
}
In the host application, I have added the following line to the AssemblyInfo.cs class: [assembly: log4net.Config.XmlConfigurator(Watch = true)]
Finally, this is the content of my app.config file:
<configuration>
<configSections>
<section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler,Log4net"/>
</configSections>
<log4net>
<appender name="TestAppender" type="log4net.Appender.RollingFileAppender" >
<file value=".\Log Directory\MyTestAppender.log" />
<encoding value="utf-8" />
<appendToFile value="true" />
<rollingStyle value="Date" />
<rollingStyle value="Size" />
<maxSizeRollBackups value="5" />
<maximumFileSize value="2MB" />
<staticLogFileName value="true" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date [%thread] %-5level %logger [%M %C] - %message%newline" />
</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>
<startup>
<supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.6.1" />
</startup>
</configuration>
I have to be missing something, but what? Keep in mind that logging works fine from the host application...
**** EDIT ********************************************************************
I think I may know what is going on here. The .dll file produced by this project runs BEFORE the host project runs because it is part of the installation script. I think the host project has to run first to initialize the log4net configurations. When I call the method in the .dll file FROM the host application, and not from the installer package, the log4net logging works just fine. Does anyone know if this is root cause, and how I can get around this?

<supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.6.1" />, Can you check your Target Framework in Assembly properties?
I just compared with my config file, I have this <log4net debug="true">. Could you please add this?

Log4net Configuration Issue

Had something weird start happening to me today. I have an asp.net mvc app with log4net setup and everything had been working fine. Something must have changed somewhere and now nothing is getting logged (no log file is being created).
Here's my global.asax.cx
protected void Application_Start()
{
log4net.Config.XmlConfigurator.Configure();
}
Here's my configuration in my web.config:
<configSections>
<section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler, log4net"/>
</configSections>
<log4net>
<appender name="FileAppender" type="log4net.Appender.RollingFileAppender">
<file value="c:\logs\api\ApiLog.txt" />
<appendToFile value="true" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date - %message%newline" />
</layout>
</appender>
<root>
<level value="ALL" />
<appender-ref ref="FileAppender" />
</root>
</log4net>
For some reason the c:\logs\api\apilog.txt file never gets created. However, if I change my application_start method to this it works fine:
log4net.Config.XmlConfigurator.Configure(new FileInfo("DirectPathToMy\web.config"));
Any ideas why calling Configure() is not finding the configuration in my web.config by default?

Don't know why your approach don't work but the issue is that you need to make sure it is activated in your project.
I usually put this as an assembly level reference in my AssemblyInfo.cs under /Properties:
[assembly: log4net.Config.XmlConfigurator()]
Reference:
http://logging.apache.org/log4net/release/manual/configuration.html

Configuring/Installing log4net for RavenDB in Visual Studio 2010

I'm trying to configure my C# project to use log4net for RavenDB. I already have log4net working with a FileAppender, but the RavenAppender doesn't seem to be working right now. The following are the steps I have taken so far:
Step 1: Installing log4net.Raven
I installed the log4net.Raven library using the following NuGet Package Manager console instructions (taken from the package website linked to above):
Install-Package log4net.Raven
That command added the log4net.Raven library to my project references.
Step 2: Configuring Web.config
In my Web.config file, I have the following settings, most of which are copy and pasted from the README file for the log4net.Raven project on GitHub (the owner of log4net.Raven also has similar configuration settings published on his blog):
<!-- Example connection string config from blog -->
<configsections>
<section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler, log4net">
</configsections>
<connectionstrings>
<add connectionstring="Url=http://raven; DefaultDatabase=Log" name="RavenLogs">
<add connectionstring="Url=http://localhost:8080;user=asa;password=asa" name="SecureRaven">
</add>
</add>
</connectionstrings>
<!-- My current config -->
<configSections>
<section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler, log4net"/>
</configSections>
<connectionStrings>
<add name="RavenDB" connectionString="Url=http://localhost:8080;Database=MyDatabase" />
</connectionStrings>
<!-- Example log4net config from README.
My project uses these settings except for the connectionString value,
which is set to "RavenDB" to match the setting name above.
-->
<log4net>
<appender name="LogFileAppender" type="log4net.Appender.FileAppender">
<!-- LogFileAppender settings here -->
</appender>
<appender name="RavenAppender" type="log4net.Raven.RavenAppender">
<filter type="log4net.Filter.LevelRangeFilter">
<levelMin value="INFO" />
<levelMax value="FATAL" />
</filter>
<connectionString value="RavenDB"/>
<maxNumberOfRequestsPerSession value="100"/>
<bufferSize value="50" />
<evaluator type="log4net.Core.LevelEvaluator">
<threshold value="ERROR" />
</evaluator>
</appender>
<root>
<level value="ALL"/>
<appender-ref ref="LogFileAppender" />
<appender-ref ref="RavenAppender" />
</root>
</log4net>
Step 3: Logging from C# code
In my C# code, I have the following:
public class FooController : Controller
{
private static ILog _log = LogManager.GetLogger(typeof(FooController));
public ActionResult Index()
{
_log.Info("Hello World!");
return View("Index");
}
}
That code will write out to a log file on my workstation, so from that I know that log4net in general is working correctly. But for RavenDB, I've been checking the Documents and Logs for MyDatabase through the Raven studio in a web browser, and I do not see any Info level log with the message "Hello World".
Does anyone have any ideas of what the problem could be and how to fix it?

May be the problem is here:
<appender name="LogFileAppender" type="log4net.Appender.FileAppender">
if you don't have class named FileAppender in your project you need to add the library name where FileAppender is, for example:
<appender name="LogFileAppender"
type="log4net.Appender.FileAppender, log4net.Raven">
(the syntax for type is =" Fully qualified class name , assembly file name , version , culture , public key token ")

Try debug log4net as here Log4Net Troubleshooting
If you find this line:
log4net: Adding appender named [RavenAppender] to logger [root].
RavenAppender is working

How to include log4net for a class library?

I want to implement logging function into a class library, which is itself referenced in a webservice. I tried to add app.config and did everything needed, but it seems that when an exception is thrown, log4net simply does nothing.
my app.config
<configSections>
<section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler, log4net"/>
</configSections>
<log4net>
<appender name="RollingFileAppender" type="log4net.Appender.RollingFileAppender">
<file value="D:\\mylogfile.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="INFO"/>
<appender-ref ref="RollingFileAppender"/>
<appender-ref ref="ConsoleAppender" />
</root>
</log4net>
in AssemblyInfo.cs:
[assembly: log4net.Config.XmlConfigurator(ConfigFile = "app.config")]
in LogManager.cs:
private static readonly ILog Log = log4net.LogManager.GetLogger
(MethodBase.GetCurrentMethod().DeclaringType);
public static void WriteLog(Exception ex)
{
Log.Error(ex);
}
Can you please tell me what's wrong? How can I get log4net working for my class library?
Thank you

At runtime, config file is always used from host application, unless declared explicitly. Here in case, web.config is being used not app.cofig. Rather mention some other custom config file name and ensure that file is copied in virtual directory of web service. Also as chibacity said, ensure permission on log file. Better keep it in app_data folder for web service host.

You could use some kind of injection, either you build a simple one like:
public interface ILogger
{
void LogInfo(string message);
.
.
.
}
And then you just inject something that matches that interface, like a wrapper for log4net or such.
But, I think the most correct thing is to not log in the class library. Why I think so is because the library itself is not the application, your web service is so your web service should decide what to log. If you want to log exceptions just don't catch them in the class library and let your web service handle the logging. This will also make it easier to centralize the logging.

Please see my answer to the following question:
Use log4net in SDK
It has a log configuration routine that will construct a complete path to a log4net config file. As you are in a webservice it my not be looking where you expect for "app.config".
Also make sure that you have permission to write to "D:\mylogfile.txt" from your webservice.