Question

Given that you have

[assembly: log4net.Config.XmlConfigurator(ConfigFile = "Log4Net.config", Watch = true)]

in your AssemblyInfo.cs file, when is Log4Net configured? Is it at the application start or when you use a logger for the first time?

Answer 1

The config file is used when you cause a call to the LoggerManager class. This is usually caused by calling LogManager.GetLogger.

See http://logging.apache.org/log4net/release/sdk/log4net.Config.XmlConfiguratorAttribute.html for more details; specifically the note:

Log4net will only look for assembly
level configuration attributes once.
When using the log4net assembly level
attributes to control the
configuration of log4net you must
ensure that the first call to any of
the LoggerManager methods is made from
the assembly with the configuration
attributes.