NFireLogger is .net server-side library for FireLogger.

It's available as NuGet package:

Sorry, FireLogger works only under Firefox.


Some examples

Basic usage

Easiest way is to use static class FLog. There are 5 log levels.

FLog.Debug("DEBUG log level");
FLog.Info("INFO log level");
FLog.Error("ERROR log level");
FLog.Warning("WARNING level");
FLog.Critical("CRITICAL log level");

Each has formatted version:

FLog.Info("Request from {0} arrived at {1}", Request.UserHostAddress, DateTime.Now);

Named Logger

var logger = FLog.GetLogger("MyLogger");

logger.Debug("This is logged as MyLogger");
logger.Warning("... and also this.");


There is method for exception logging.

catch (Exception ex)

Log4net Support

There is FireLogger appender for log4net.

It's available also as NuGet package:


You have to add appender NFireLogger.Log4net.FireLoggerAppender to your log4net configuration. E.g.:

<appender name="FireLogger" type="NFireLogger.Log4net.FireLoggerAppender, NFireLogger.Log4net">
    <layout type="log4net.Layout.PatternLayout">
        <conversionPattern value=%message" />


After that you can use log4net as usual

var l = LogManager.GetLogger("log4net");

l.Info("Info message from log4net");
l.DebugFormat("and debug message at {0}", DateTime.Now.ToShortTimeString());


There are 2 configurations that can be put in appSettings section in web.config:

Specify password for FireLogger authentication. Default: ""
All internal errors of FireLogger are thrown away if this is set to true. Otherwise it's logged by standard Trace technique. Default: true
In every log there will be file name and line number information it this is set to true. Default: true
        <add key="NFireLogger.Password" value="password" />
        <add key="NFireLogger.Silent" value="true" />
        <add key="NFireLogger.LogFileInfo" value="true" />

Manual Setup

If you don’t want to use NuGet, here is manual setup:

1 Add reference for NFireLogger.dll to your project.

2 Add HttpModul NFireLogger.FireLoggerHttpModule to your web.config.

For IIS7 in Integrated mode it looks like this:

        <add name="FireLoggerHttpModule" type="NFireLogger.FireLoggerHttpModule"/>

For Standard mode or IIS6 look at documentation for server.

3 Done! Now you can use FLog.

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