Questions tagged [log4net]

The Apache log4net library is a tool to help the programmer output log statements to a variety of output targets. log4net is a port of the excellent Apache log4j™ framework to the Microsoft® .NET runtime. We have kept the framework similar in spirit to the original log4j while taking advantage of new features in the .NET runtime.

Apache log4net is a tool to help the programmer output log statements to a variety of output targets. In case of problems with an application, it is helpful to enable logging so that the problem can be located. With log4net it is possible to enable logging at runtime without modifying the application binary. The log4net package is designed so that log statements can remain in shipped code without incurring a high performance cost. It follows that the speed of logging (or rather not logging) is crucial.

At the same time, log output can be so voluminous that it quickly becomes overwhelming. One of the distinctive features of log4net is the notion of hierarchical loggers. Using these loggers it is possible to selectively control which log statements are output at arbitrary granularity.

log4net is designed with two distinct goals in mind: speed and flexibility.

Features:

  • Support for multiple frameworks
  • Output to multiple logging targets
  • Hierarchical logging architecture
  • XML Configuration
  • Dynamic Configuration
  • Logging Context
  • Proven architecture
  • Modular and extensible design
  • High performance with flexibility

Support for multiple frameworks:

log4net runs on all ECMA CLI 1.0 compatible runtimes. log4net has specific builds for the following frameworks:

  • Microsoft® .NET Framework 1.0
  • Microsoft .NET Framework 1.1
  • Microsoft .NET Framework 2.0
  • Microsoft .NET Framework 3.5
  • Microsoft .NET Framework 4.0
  • Microsoft .NET Framework 3.5 Client Profile
  • Microsoft .NET Framework 4.0 Client Profile
  • Microsoft .NET Compact Framework 1.0*
  • Microsoft .NET Compact Framework 2.0
  • Mono 1.0
  • Mono 2.0
  • Microsoft Shared Source CLI 1.0*
  • CLI 1.0 Compatible
  • Microsoft .NET Core 1.0 providing .NET Standard 1.3

The "Client Profile" builds are stripped down versions of the "normal" builds that don't contain any ASP.NET releated code - which for example means the %aspnet-* patterns and the AspNetTraceAppender are not available.

* Not supported by the binary release but can be built from the source release.

Official Website: http://logging.apache.org/log4net/

Useful Links:

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Log4Net - How to add a 2nd logger used only for specific sections of code

I'm using Log4Net 2.0, I have it working as required but which to add another logger for specific log statements. All logging is done to a single file appender. The change I want to make is that a 3rd party application fires events containing…
JonWillis
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How to log SQL calls with NHibernate to the console of Visual Studio?

I have the following configuration file for NHibernate:
Nicolas Cadilhac
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When logging when is an error fatal?

In logging frameworks like log4j & log4net you have the ability to log various levels of information. Most of the levels have obvious intentions (such as what a "Debug" log is vs. a "Error"). However, one thing that I have always been timid on was…
Jason Whitehorn
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unable to get log4net working with .net windows service

I have a windows service with an app.config and a log4net.config. app.config:
Null Reference
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Maximum Filesize of LogFileAppender in Log4Net

I am using Log4net for a while now and it's an amazing logging framework, especially when hooked into Castle.Windsor. However... I usually use the rolling file appender, but this has resulted in too many log files than I actually want, so instead,…
Ash
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Log4net randomly stops logging.

I am currently building an ASP.Net-MVC Application using log4net for logging, but the logger seems to just stop at random. It will happily log for awhile, and then stop, and then will start again after a period of time. I am not even sure what it is…
Jacob Bellamy
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Log4Net with Application Insights

I am trying to configure my azure asp.net website to send log4net traces to Azure Application Insights. I can see in my azure console page views etc, hence I know that is working fine. I can also see log4net traces, when configured with a file…
BMac
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Log4Net: Programmatically specify multiple loggers (with multiple file appenders)

How to (programmatically, without xml config) configure multiple loggers with Log4Net? I need them to write to different files.
Jox
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Is there a user-friendly Log4Net log files viewer?

Is there any third party tool that can recognize Log4Net log file structure and show it in a user friendly way by providing search functionalities etc?
pencilCake
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Why isn't there a trace level in log4Net?

I was just wondering why there isn't a trace level in log4Net. This level seems to be missing and I sometimes feel the need to use it, for example to output what events are being executed in an application. This feature is a part of log4J. I know I…
armannvg
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How to specify common application data folder for log4net?

I want log4net to write log files (using RollingFileAppender) to a subfolder of the common application data folder (e.g. C:\Documents and Settings\All Users\Application Data\Company\Product\Logs). However, on Win XP, there is no environment variable…
user57474
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Log4Net: Log with UTC times

Using log4net 1.2.11.0 w/ .NET, how can I get the RollingFileAppender to output UTC dates? According to Apache it should be as easy as: Unfortunately this is not…
Kevin Kalitowski
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Log4net configuration from assembly attribute does not load configuration file

I have the following file Log4net.config in my bin directory:
Chris
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How to log MethodName when wrapping Log4net?

I have wrapped Log4net in a static wrapper and want to log loggingEvent.LocationInformation.MethodName loggingEvent.LocationInformation.ClassName However all I get is the name of my wrapper. How can I log that info using a forwardingappender…
Claus Thomsen
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Send an Email When an Error Occurs in C# using log4net

Currently my application is using log4net to log errors, the web.config for this is as followed:
swade1987
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