log4net: How to set logger file name dynamically? - dynamic

Question

This is a really common question, but I have not been able to get an answer to work. Here is my configuration file:
<?xml version="1.0" encoding="utf-8"?>
<log4net>
<appender name="RollingFile" type="log4net.Appender.RollingFileAppender">
<file value="CraneUserInterface.log" />
<appendToFile value="true" />
<maxSizeRollBackups value="90" />
<rollingStyle value="Size" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date - %message%newline" />
</layout>
</appender>
<root>
<level value="DEBUG" />
<appender-ref ref="RollingFile" />
</root>
But I need to determine the actual logging file name at run time. I found a nice example here, but when I try to loop through the collection returned by the call to GetIterators(), I find that that collection is empty.
I need to change the name "CraneUserInterface.log" to "CraneUserInterface_1.log", or 2, or 3, depending on something the program reads at run time. How can I do that?
Here's my first pass at using the code presented in that sample:
static bool ChangeLogFileName(string AppenderName, string NewFilename)
{
// log4net.Repository.ILoggerRepository RootRep;
// RootRep = log4net.LogManager.GetRepository();
log4net.Repository.ILoggerRepository RootRep = m_logger.Logger.Repository;
foreach (log4net.Appender.IAppender iApp in RootRep.GetAppenders())
{
string appenderName = iApp.Name;
if (iApp.Name.CompareTo(AppenderName) == 0
&& iApp is log4net.Appender.FileAppender)
{
log4net.Appender.FileAppender fApp = (log4net.Appender.FileAppender)iApp;
fApp.File = NewFilename;
fApp.ActivateOptions();
return true; // Appender found and name changed to NewFilename
}
}
return false; // appender not found
}
Thanks very much!

Answer 1

What about to use "%property" to define a dynamic 'tag' to the file name (at runtime) ?
<file type="log4net.Util.PatternString" value="~/App_Data/%property{LogName}" />
Explained here: Best way to dynamically set an appender file path

Answer 2

you can use this function :
in this function first get file location that you set in webconfig and after that you can add any path that you want ! like Date ! our Customer ! or .....
WebConfig:
<appender name="RollingLogFileAppender" type="log4net.Appender.RollingFileAppender">
<file value="C:\\t4\\"/>
<appendToFile value="true"/>
<rollingStyle value="Composite"/>
<datePattern value="_yyyy-MM-dd.lo'g'"/>
<maxSizeRollBackups value="10"/>
<maximumFileSize value="1MB"/>
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date User:%identity IP:%X{addr} Browser: %X{browser} Url: %X{url} [%thread] %-5level %c:%m%n"/>
</layout>
</appender>
Function:
public static void ChangeFileLocation(string _CustomerName,string _Project)
{
XmlConfigurator.Configure();
log4net.Repository.Hierarchy.Hierarchy h =(log4net.Repository.Hierarchy.Hierarchy)LogManager.GetRepository();
foreach (IAppender a in h.Root.Appenders)
{
if (a is FileAppender)
{
FileAppender fa = (FileAppender)a;
string sNowDate= DateTime.Now.ToLongDateString();
// Programmatically set this to the desired location here
string FileLocationinWebConfig = fa.File;
string logFileLocation = FileLocationinWebConfig + _Project + "\\" + _CustomerName + "\\" + sNowDate + ".log";
fa.File = logFileLocation;
fa.ActivateOptions();
break;
}
}
}
and result like this : C:\t4\TestProject\Customer1\Saturday, August 31, 2013.log